Blocked operation for group ii and group iii lubricant production

ABSTRACT

Systems and methods are provided for block processing of a feedstock to produce multiple viscosity grades of lubricant base stocks with substantially different viscosity index values. The systems and methods can involve the use of a sweet stage hydrocracking catalyst that can maintain good aromatic saturation activity under conditions that produce substantially different levels of viscosity index uplift. Optionally, the reactor including the sweet stage hydrocracking catalyst can include additional aromatic saturation catalyst. The systems and methods can further involve using a combination of aromatic saturation catalyst and dewaxing catalyst in a second sweet stage reactor, so that additional aromatic saturation activity is available for saturation of aromatics for products that undergo lower amounts of conversion in the sweet hydrocracking stage. The systems and methods can also allow for increased control over the relative temperatures of reactors within a reaction system.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No.62/540,658 filed on Aug. 3, 2017, the entire contents of which areincorporated herein by reference.

FIELD

Systems and methods are provided for production of lubricant oil basestocks using a processing train in blocked operation. The systems andmethods allow for production of Group II and Group III lubricant basestocks from a feed.

BACKGROUND

Lubricant base stocks are one of the higher value products that can begenerated from a crude oil or crude oil fraction. The ability togenerate lubricant base stocks of a desired quality is often constrainedby the availability of a suitable feedstock. For example, mostconventional processes for lubricant base stock production involvestarting with a crude fraction that has not been previously processedunder severe conditions, such as a virgin gas oil fraction from a crudewith moderate to low levels of initial sulfur content.

A number of challenges in production of lubricant base stocks arerelated to the competing desires of generating as high a yield of basestocks as possible while also meeting target specifications for multipletypes of base stocks. For example, it can be desirable to produce bothlight neutral and medium/heavy neutral grades of lubricant base stocksfrom a single feed. Unfortunately, the processing conditions requiredfor meeting the product specifications for a light neutral lubricantbase stock are often substantially higher in severity than theprocessing conditions for meeting the product specifications for amedium neutral or heavy neutral base stock. Processing the feed at thehigher severity conditions can lead to additional feed conversion,resulting in overall loss in lubricant yield.

U.S. Patent Application Publication 2011/0315596 describes an integratedprocess for hydrocracking and dewaxing of hydrocarbons to form naphtha,diesel, and/or lubricant base stock boiling range products. Theintegrated process includes dewaxing and optionally hydrocracking undersour conditions, a separation to form a first diesel product and abottoms product, and additional hydrocracking and dewaxing to form asecond diesel product and optionally a lubricant base oil product. Thehydrocracking and dewaxing catalysts can include base metals or caninclude Pd and/or Pt. An example of a hydrocracking catalyst is USY andan example of a dewaxing catalyst is ZSM-48.

U.S. Pat. No. 8,932,454 describes a method of making and using a Yzeolite hydrocracking catalyst. The Y zeolite catalyst has a smallmesoporous peak in the pore size distribution of around 40 Å as measuredby nitrogen desorption.

U.S. Pat. No. 8,778,171 describes a method of making and using a Yzeolite hydrocracking catalyst. The Y zeolite catalyst containsstabilized aggregates of Y zeolite primary crystallites having a size of0.5 microns or less.

U.S. Patent Application Publication 2013/0341243 describes ahydrocracking process selective for improved distillate and improvedlube yield and properties. A two-stage hydrocracking catalyst can beused for hydrocracking of a feed to form a converted portion suitablefor diesel fuel production and an unconverted portion suitable forproduction of lubricant base stocks. The two-stage hydrocrackingcatalyst can correspond to a first stage catalyst including Pd and/or Ptsupported on USY and a second stage catalyst including Pd and/or Ptsupported on ZSM-48.

SUMMARY

In various aspects, methods are provided for producing lubricant boilingrange product using blocked operation. The methods can includefractionating a hydroprocessed feedstock to form at least a firstlubricant boiling range fraction comprising a 343° C.+ portion and asecond lubricant boiling range fraction having a T10 distillation pointof at least 343° C. and a kinematic viscosity at 100° C. of 6.0 cSt ormore. The 343° C.+ portion of the first lubricant boiling range fractioncan have a kinematic viscosity at 100° C. of 1.5 cSt to 6.0 cSt. Thesecond lubricant boiling range fraction can optionally have a viscosityindex that is greater than the viscosity index of the first lubricantboiling range fraction. The first lubricant boiling range fraction andthe second lubricant boiling range fraction can be processed based onblock operation of a reaction system. For example, At least a portion ofthe first lubricant boiling range fraction can be hydrocracked in thepresence of hydrocracking catalyst under first hydrocracking conditionsin a first reactor to form a first hydrocracked effluent. The firsthydrocracking conditions can include a first hydrocracking inlettemperature and a first hydrocracking outlet temperature. The firsthydrocracking conditions can correspond to conditions for 10 wt % to 80wt % conversion relative to 370° C. of the at least a portion of thefirst lubricant boiling range fraction. At least a portion of the firsthydrocracked effluent can be dewaxed under first catalytic dewaxingconditions in a second reactor to form a first dewaxed effluent. Thesecond lubricant boiling range product can also be hydrocracked, butunder second hydrocracking conditions. The second hydrocrackingconditions can include 1 wt % to 25 wt % conversion relative to 370° C.of the at least a portion of the second lubricant boiling rangefraction, along with a second hydrocracking inlet temperature and asecond hydrocracking outlet temperature. The conversion relative to 370°C. for the first hydrocracking conditions can be at least 10 wt %greater than the conversion relative to 370° C. for the secondhydrocracking conditions. At least a portion of the second hydrocrackedeffluent can be dewaxed under second catalytic dewaxing conditions inthe second reactor to form a second dewaxed effluent. At least a portionof the first dewaxed effluent can be fractionated to form at least afirst fuels boiling range product and a first lubricant boiling rangeproduct. Similarly, at least a portion of the second dewaxed effluentcan be fractionated to form at least a second fuels boiling rangeproduct and a second lubricant boiling range product. A viscosity indexof the second lubricant boiling range product can being lower than aviscosity index of the first lubricant boiling range product by at least5.

In some aspects, the hydroprocessed feedstock can be formed byhydroprocessing a feedstock under hydroprocessing conditions.Optionally, instead of fractionating the hydroprocessed feedstock, blockprocessing can also be used for the initial hydroprocessing of thefeedstock. In such aspects, an initial feedstock can be fractionated toform at least a first lubricant boiling range fraction comprising a 343°C.+ portion and a second lubricant boiling range fraction having a T10distillation point of at least 343° C. and a kinematic viscosity at 100°C. of 6.0 cSt or more, the 343° C.+ portion having a kinematic viscosityat 100° C. of 1.5 cSt to 6.0 cSt. In this type of aspect, the firstlubricant boiling range fraction and the second lubricant boiling rangefraction can be processed separately to form hydroprocessed lubricantboiling range fractions for subsequent hydrocracking and dewaxing.

In some aspects, the second catalytic dewaxing conditions can include asecond dewaxing inlet temperature that is greater than the secondhydrocracking outlet temperature, while the first catalytic dewaxingconditions can include a first dewaxing inlet temperature that is lessthan the first hydrocracking outlet temperature. This type of controlover the dewaxing inlet temperature can be facilitated, for example, byintroducing a heated hydrogen-containing stream into the second reactorduring the second catalytic dewaxing conditions.

In some aspects, the block processing of the feeds can be facilitated bystoring the at least a portion of the first lubricant boiling rangefraction prior to the hydrocracking of the at least a portion of thefirst lubricant boiling range fraction, ii) further comprising storingthe at least a portion of the second lubricant boiling range fractionprior to the hydrocracking of the at least a portion of the secondlubricant boiling range fraction, or iii) a combination of i) and ii).

In some aspects, the first reactor can further include an aromaticsaturation catalyst, and/or the second reactor further can furtherinclude an aromatic saturation catalyst.

In some aspects, the first lubricant boiling range product can have aviscosity index of at least 125. Additionally or alternately, the secondlubricant boiling range product can have a viscosity index of at least80. Additionally or alternately, the viscosity index of the secondlubricant boiling range product can be lower than the viscosity index ofthe first lubricant boiling range product by at least 15.

In some aspects, the first dewaxing conditions can be substantiallysimilar to the second dewaxing conditions. In some aspects, the firsthydrocracking inlet temperature can be greater than the secondhydrocracking inlet temperature by at least 10° C.

Optionally, the method can further include exposing at least a portionof the first dewaxed effluent to an aromatic saturation catalyst in athird reactor under first aromatic saturation conditions to form a firstsaturated product comprising the first lubricant boiling range product.In such aspects, the first lubricant boiling range product can have anaromatics content of 2.0 wt % or less. Optionally, the method can alsofurther include exposing at least a portion of the second dewaxedeffluent to the aromatic saturation catalyst in the third reactor undersecond aromatic saturation conditions to form a second saturated productcomprising the second lubricant boiling range product. The secondlubricant boiling range product can have an aromatics content of 2.0 wt% or less. The first aromatic saturation conditions can optionally besubstantially similar to the second aromatic saturation conditions. Thesecond reactor can optionally further comprise a second aromaticsaturation catalyst, the at least a portion of the first hydrocrackedeffluent contacting at least a portion of the second aromatic saturationcatalyst prior to being exposed to the dewaxing catalyst.

In various aspects, a multi-reactor reaction system is provided. Themulti-reactor reaction system can include a first reactor comprising afirst gas inlet, a hydrocracking reactor inlet, and a hydrocrackingreactor outlet. The first reactor can also include a hydrocrackingcatalyst comprising 0.1 wt % to 5.0 wt % of a Group 8-10 noble metalsupported on the hydrocracking catalyst. The system can further includea second reactor comprising a second gas inlet, a dewaxing reactorinlet, and a dewaxing reactor outlet. The second reactor can furtherinclude a dewaxing catalyst. The dewaxing reactor inlet can be in fluidcommunication with the hydrocracking reactor outlet. The system canfurther include a third reactor comprising an aromatic saturation inlet,an aromatic saturation outlet, and a first aromatic saturation catalyst.The aromatic saturation inlet can be in fluid communication with thedewaxing reactor outlet. The system can further include a heater havinga feed heater flow path and a hydrogen heater flow path. The feed heaterflow path can be in fluid communication with the hydrocracking reactorinlet. The hydrogen heater flow path can be in fluid communication withthe first gas inlet and the second gas inlet. Optionally, at least aportion of a second aromatic saturation catalyst can be located upstreamfrom the dewaxing catalyst relative to a direction of flow in the secondreactor. Optionally, the system can further include a third reactor thatincludes a third gas inlet in fluid communication with the hydrogenheater flow path.

In some aspects, the hydrocracking reactor inlet can correspond to thefirst gas inlet. In some aspects, the second gas inlet can be inselective fluid communication with the heated hydrogen flow path.

Optionally, the system can further include a first storage tank and asecond storage tank. the first storage tank and the second storage tankcan be in selective fluid communication with the feed heater flow path.The first storage tank can store the first lubricant boiling range feedand the second storage tank can store the second lubricant boiling rangefeed.

In various aspects, a method for producing a lubricant boiling rangeproduct is provided. The method can include hydrocracking a lubricantboiling range fraction in the presence of hydrocracking catalyst underfirst hydrocracking conditions in a first reactor to form a firsthydrocracked effluent. The first hydrocracking conditions can correspondto a first amount of conversion relative to 370° C. of the lubricantboiling range fraction. At least a portion of the first hydrocrackedeffluent can be dewaxed under first catalytic dewaxing conditions in asecond reactor to form a first dewaxed effluent. The first dewaxinginlet temperature can be greater than the first hydrocracking outlettemperature by at least 3° C. The conditions for hydrocracking can thenbe modified while performing hydrocracking of the lubricant boilingrange fraction. The lubricant boiling range fraction can be hydrocrackedunder the modified hydrocracking conditions in the first reactor to forma second hydrocracked effluent. The modified hydrocracking conditionscan correspond to a second amount of conversion relative to 370° C. ofthe lubricant boiling range fraction that is different from the firstamount of conversion relative to 370° C. by 5 wt % or less. At least aportion of the second hydrocracked effluent can be dewaxed under secondcatalytic dewaxing conditions in the second reactor to form a seconddewaxed effluent. The second dewaxing inlet temperature can be less thanthe modified hydrocracking outlet temperature by at least 3° C. Theresulting first dewaxed effluent and second dewaxed effluent can befractionated to form (optional) fuels boiling range products andlubricant boiling range products. Optionally, the dewaxed effluents canbe hydrofinished before and/or after fractionation to form the lubricantboiling range products. A viscosity index of the second lubricantboiling range product can be different than a viscosity index of thefirst lubricant boiling range product by 5 or less.

The lubricant boiling range fraction can correspond to a feedstocksuitable for forming any convenient type of lubricant fraction. Forexample, the lubricant boiling range fraction can correspond to a feedfor heavy neutral base stock production, such as a feed having a T10distillation point of at least 343° C. and a kinematic viscosity at 100°C. of 6.0 cSt or more; or a feed for brightstock production, such as afeed having a T10 distillation point of at least 371° C. and a kinematicviscosity at 100° C. of 15 cSt or more; or a feed for light neutral basestock production, such as a feed having a 343° C.+ portion, the 343° C.+portion having a kinematic viscosity at 100° C. of 1.5 cSt to 6.0 cSt.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 schematically shows an example of a configuration suitable forprocessing a feedstock to form at least a lubricant boiling rangefraction.

FIG. 2 schematically shows another example of a configuration suitablefor processing a feedstock to form at least a lubricant boiling rangefraction.

FIG. 3 schematically shows another example of a configuration suitablefor processing a feedstock.

FIG. 4 schematically shows an example of a reaction system includingmultiple reactors and multiples heated hydrogen lines.

DETAILED DESCRIPTION Overview

All numerical values within the detailed description and the claimsherein are modified by “about” or “approximately” the indicated value,and take into account experimental error and variations that would beexpected by a person having ordinary skill in the art.

In various aspects, systems and methods are provided for blockprocessing of a feedstock to produce multiple viscosity grades oflubricant base stocks with substantially different viscosity indexvalues. The systems and methods can involve the use of a sweet stagehydrocracking catalyst that can maintain good aromatic saturationactivity under conditions that produce substantially different levels ofviscosity index uplift. Optionally, the reactor including the sweetstage hydrocracking catalyst can include additional aromatic saturationcatalyst. The systems and methods can further involve using acombination of aromatic saturation catalyst and dewaxing catalyst in asecond sweet stage reactor, so that additional aromatic saturationactivity is available for saturation of aromatics for products thatundergo lower amounts of conversion in the sweet hydrocracking stage.

The systems and methods described herein can allow a single reactionsystem, operated in a block processing mode, to start with a singlefeedstock and generate a light neutral and a heavy neutral product witha viscosity index difference of at least 25, or at least 30, or at least40, while also maintaining the aromatics content of both the lightneutral and the heavy neutral products at 2.0 wt % or less, or 1.0 wt %or less. Using a traditional sweet stage hydrocracking catalyst and/orusing a traditional sweet stage dewaxing reactor without substantialinitial aromatic saturation activity, achieving this desirablecombination of features (high VI difference, low aromatics content) in alight neutral and a heavy neutral product derived from a singlefeedstock would require separate processing trains.

The block processing can be further facilitated based on use of separatehot hydrogen lines for introducing heated hydrogen into two or more ofthe sweet stage reactors. A sweet stage can often include a plurality ofreactors, such as a hydrocracking reactor, a dewaxing reactor, and ahydrofinishing reactor. It can be desirable to set the temperature ofeach reactor at different levels in order to provide improved controlover processing conditions. In various aspects, additional control overprocessing conditions can be provided based on the use of heatedhydrogen lines that are introduced into subsequent reactor(s) in thesweet hydroprocessing stage. Instead of adding heat primarily in theinitial reactor and/or by heat exchange on the effluents from thereactors, the use of heated hydrogen lines can allow for additionalcontrol over the temperature of the input flows to subsequent reactorstages.

As an example, use of heated hydrogen lines can allow the sweet stagereactor train to be used for processing one feed (such as a feed forlight neutral production) during block operation with the hydrocracking(first) reactor operated at a higher outlet temperature than the inlettemperature of the dewaxing (second) reactor. By using a heated hydrogenline to deliver heated hydrogen to the second reactor during processingof a feed for heavy neutral production, the same sweet stage reactortrain can be operated to have a hydrocracking reactor outlet temperaturethat is colder than the dewaxing reactor inlet temperature. During suchheavy neutral production, the outlet temperature of the hydrocrackingreactor can be cooler than the inlet temperature of the dewaxing reactorby at least 10° C., or at least 20° C., or at least 30° C. This canallow a single sweet stage reactor train to be used for block processingwhile reducing or minimizing the yield loss due to over-cracking of thefeed for heavy neutral production.

In addition to facilitating block processing, additional control overthe inlet and outlet temperatures for reactors in a reactorconfiguration can also allow for switching of the relative temperatureprofiles for reactors during processing of a single feed. For example,in sweet processing stage for lubricant production, separate reactorscan be used for hydrocracking and dewaxing of the feed. As noted above,the temperature of the first reactor is typically selected to providethe desired temperature for the highest temperature stage in thereaction system. By allowing for increased control over the temperatureof reactors, the reactor corresponding to the “warmest” reactor can bechanged during processing of a feed. As an example, during processing ofa heavy neutral feed, a relatively low temperature may be sufficient forthe hydrocracking stage, as the amount of viscosity index upliftrequired for a heavy neutral is often small. As a result, the outlettemperature for the hydrocracking reactor can be lower than the desiredinlet temperature for dewaxing. However, as processing continues and thecatalyst is aged, increasingly higher temperatures may be needed tomaintain a desired level of viscosity index uplift. Based on thiscatalyst aging, the temperature (and/or other conditions associated withhydrocracking) can be modified during processing of the feed, in orderto maintain the properties of the resulting lubricant product in adesired range. This can eventually result in having a higher outlettemperature for the hydrocracking reactor than the inlet temperature forthe dewaxing reactor. For example, the temperature of the hydrocrackingconditions can be modified so that at a later point during processing,the viscosity index of the lubricant boiling range product differs fromthe viscosity index of the product at an earlier time by less than 5, orless than 3, or possibly even less than 1. In some aspects, aging of thedewaxing catalyst may also occur. Modifying the temperature (and/orother conditions) of the dewaxing process may also be used to maintain adesired pour point for the resulting lubricant product. For example, thetemperature of the dewaxing conditions can be modified so that at alater point during processing, the pour point of the lubricant boilingrange product differs from the pour point of the product at an earliertime by less than 10° C., or less than 6° C., or less than 3° C.

More generally, changing of the “warmest” reactor in a reactor sequencecan be used during processing of any convenient type of lubricant feed,including feeds for production of light neutral base stocks (1.5 cSt to6.0 cSt at 100° C.), feeds for production of heavy neutral base stocks(6.0 cSt to 12 cSt at 100° C., or 6.0 cSt to 15 cSt, or 6.0 cSt to 20cSt), or feeds for production of brightstock (15 cSt or more, or 20 cStor more, or 25 cSt or more, or 30 cSt or more, such as up to 50 cSt orpossibly still higher). The heated hydrogen lines described herein canfacilitate having this type of switch in the relative temperatures ofthe reactors. In various aspects, the outlet temperature of thehydrocracking reactor at an initial point in a processing run can belower than the inlet temperature of the dewaxing reactor, or at least 3°C. lower, or at least 5° C. lower, or at least 8° C. lower, or at least10° C. lower. At a later point in the processing run, the outlettemperature of the hydrocracking reactor can be higher than the inlettemperature for the dewaxing reactor, or at least 3° C. higher, or atleast 5° C. higher, or at least 8° C. higher, or at least 10° C. higher.

During processing of a feedstock for lubricant base stock production, atwo stage reaction system can be used. The first stage can correspond toa sour processing stage to reduce the sulfur content, nitrogen content,and/or content of other heteroatoms in the feedstock to a desired level.The first (sour) processing stage can be a stage where the entirefeedstock is processed. Alternatively, if it is desired, the firstprocessing stage can be operated in block processing mode. If the first(sour) processing stage is operated in block processing mode, aseparation can be performed on the feedstock to produce a first fractionthat includes the feed for the desired light neutral product and asecond fraction that includes the feed for the desired heavy neutralproduct. It is noted that due to conversion, some additional lightneutral product may be made during processing of the second fraction.Optionally, at least a portion of this additional light neutral productcan be separated from the heavy neutral product and added to the lightneutral fraction. In other aspects, any light neutral product madeduring conversion of the feed for heavy neutral production can beretained with the heavy neutral product. Based on the substantiallylower viscosity index of the heavy neutral product, it may not bedesirable to separate a portion of the lower viscosity index product forcombination with the higher viscosity index light neutral product.

When selecting conditions for hydrotreating and/or hydrocracking in thefirst stage, the conditions can be selected to achieve two goals. First,the heteroatom content of the feed can be reduced to a desired amount,as noted above. Second, the severity of the first stage conditions canbe selected to provide a desired amount of feed conversion, such asconversion relative to 370° C., so that the 343° C.+ portion of thefirst stage effluent has a desired viscosity index. Depending on theaspect, the 343° C.+ portion of the first stage effluent can have aviscosity index of 70-90. Additionally or alternately, afterfractionation of the first stage effluent to form feeds for blockedoperation in the second stage, the 343° C.+ portion of the feed to thesecond stage for production of a light neutral fraction can have aviscosity index of 65-90 while the feed to the second stage forproduction of a heavy neutral fraction can have a viscosity index of70-90, or 75-95. In various aspects, the viscosity index of the feed tothe second stage for production of a heavy neutral can have a viscosityindex that is at least 3 greater than the corresponding feed forproduction of a light neutral, or at least 5 greater, or at least 8greater, such as up to 15 greater or more. In optional aspects where thefirst stage feed is blocked, the feed for light neutral production andthe feed for heavy neutral production can be processed separately in thefirst stage and in the second stage. In such optional aspects, theviscosity index of the feed to the first stage for light neutralproduction and/or the viscosity index of the feed to the first stage forheavy neutral production can be 10 to 70 (or possibly higher, such as 10to 90).

During blocked operation of the second stage, the amount of conversionfor each feed can be selected to achieve a desired amount of viscosityindex uplift. For a feed for light neutral base stock production, theamount of conversion relative to 370° C. can be 10 wt % to 80 wt %, or40 wt % to 80 wt %, or 20 wt % to 60 wt %, or 40 wt % to 70 wt %. Thisamount of conversion can allow for production (after finalfractionation) of a light neutral base stock product having a kinematicviscosity at 100° C. of 1.5 cSt to 6.0 cSt, or 2.0 cSt to 6.0 cSt ormore, or 2.0 cSt to 5.0 cSt, or 1.5 cSt to 4.0 cSt or more. The lightneutral base stock product can have a viscosity index of 120-140, or125-145, or 130-150. For a feed for heavy neutral base stock production,the amount of conversion relative to 370° C. can be 1 wt % to 25 wt %,or 5 wt % to 25 wt %, or 1 wt % to 20 wt %. This amount of conversioncan allow for production (after final fractionation) of a heavy neutralbase stock product having a kinematic viscosity at 100° C. of 6.0 cSt ormore, or 6.5 cSt or more, or 8.0 cSt or more, such as up to 16 cSt orpossibly still higher. The heavy neutral base stock product can have aviscosity index of 80-100, or 80-95, or 85-100. In various aspects, theviscosity index of the light neutral base stock product can be at least5 greater than the corresponding heavy neutral base stock product, or atleast 15 greater, or at least 25 greater, or at least 35 greater, suchas up to 50 greater or more. Additionally, the amount of conversion forthe feed for light neutral production can be at least 10 wt % greaterthan the amount of conversion for the feed for heavy neutral production,or at least 15 wt % greater, or at least 20 wt % greater.

In order to achieve a desired difference in the conversion amounts, theinlet temperature for hydrocracking for the feed for light neutralproduction can be at least 10° C. higher than the inlet temperature forhydrocracking for the feed for heavy neutral production, or at least 15°C. higher, or at least 20° C. higher, such as up to 40° C. higher orpossibly still more. Optionally, the relatively temperatures of thereactors within the second stage can be changed due to the differencesin hydrocracking inlet temperatures. For example, the hydrocrackinginlet temperature for production of a light neutral base stock cantypically be greater than the dewaxing inlet temperature. However, basedon the ability to independently heat subsequent reactors, thehydrocracking inlet temperature for production of a heavy neutral basestock can optionally be colder than the dewaxing inlet temperature.Depending on the aspect, the dewaxing inlet temperature can be 1° C. ormore higher than the hydrocracking exit temperature, or 10° C. or moregreater, or 20° C. or more greater, or 30° C. or more greater, such asup to 45° C. greater (or possibly a still larger difference).

Greater flexibility can be available when selecting conditions forhydrotreating and/or hydrocracking during blocked operation of both thefirst stage and the second stage. The amount of conversion in the firststage can still be sufficient to reduce the heteroatom content of thefeed can be reduced to a desired amount, so that the second stage can beoperated under sweet conditions. However, higher amounts of conversionthan necessary for heteroatom removal could be selected in the firststage. So long as the second stage is processed under sweet conditionsand the target viscosity and viscosity index are achieved, anyconvenient balance of conversion between the first and second stages canbe used for each feed that is block processed. For example, in someaspects it may be convenient to reduce the first stage conversion for afeed for heavy neutral production to the minimum value for heteroatomremoval. This can allow additional conversion to be performed in thesecond stage, which may simplify selection of temperatures for thevarious reactors in the second stage. Similarly, performing additionalconversion in the first stage for processing a feed for light neutralproduction may be beneficial to reduce the conversion requirements inthe second stage. The availability of heated hydrogen lines tosubsequent reactors in the first stage and/or the second stage can allowfor flexibility in selecting temperatures for the reactors in the secondstage, so that the link between the inlet temperature for conversionreactors and the inlet temperature of other reactors can be reduced orminimized.

During blocked operation of both the first stage and the second stage,the amount of conversion for each feed can be selected to achieve adesired amount of viscosity index uplift. For a feed for light neutralbase stock production, the combined amount of conversion relative to370° C. across both the sour stage and the sweet stage can be 40 wt % to80 wt %, or 50 wt % to 80 wt %, or 40 wt % to 70 wt %. This amount ofconversion can allow for production (after final fractionation) of alight neutral base stock product having a kinematic viscosity at 100° C.of 1.5 cSt to 6.0 cSt, or 2.0 cSt to 6.0 cSt or more, or 2.0 cSt to 5.0cSt, or 1.5 cSt to 4.0 cSt or more. The light neutral base stock productcan have a viscosity index of 120-140, or 125-145, or 130-150. For afeed for heavy neutral base stock production, the combined amount ofconversion relative to 370° C. across both the sour stage and the sweetstage can be 20 wt % to 60 wt %, or 30 wt % to 50 wt %, or 20 wt % to 40wt %. This amount of conversion can allow for production (after finalfractionation) of a heavy neutral base stock product having a kinematicviscosity at 100° C. of 6.0 cSt or more, or 6.5 cSt or more, or 8.0 cStor more, such as up to 16 cSt or possibly still higher. The heavyneutral base stock product can have a viscosity index of 80-100, or80-95, or 85-100. In various aspects, the viscosity index of the lightneutral base stock product can be at least 5 greater than thecorresponding heavy neutral base stock product, or at least 15 greater,or at least 25 greater, or at least 35 greater, such as up to 50 greateror more. Additionally, the combined amount of conversion across both thesour stage and the sweet stage for the feed for light neutral productioncan be at least 10 wt % greater than the combined amount of conversionfor the feed for heavy neutral production, or at least 15 wt % greater,or at least 20 wt % greater.

Conventionally, some difficulties in attempting to select processconditions during block processing of lubricant feeds can be related tothe competing goals of achieving a desired viscosity index for a lightneutral base stock while achieving one or more desired cold flowproperties for a heavy neutral base stock. For light neutral base stockproduction, it can be beneficial to perform hydrocracking at relativelyhigher temperatures, in order to provide increased conversion andtherefore increased viscosity index uplift. Based on the relativelyhigher temperature in the hydrocracking reactor, the effluent fromhydrocracking can be at a temperature to allow for dewaxing to achievedesired cold flow properties. By contrast, the viscosity index of a feedfor heavy neutral base stock production can often require little or noadditional viscosity index uplift in order to meet a desired productviscosity index. Therefore, it would be desirable to pass the feed forheavy neutral production through the hydrocracking reactor at arelatively lower temperature, in order to reduce or minimize yield lossthat can occur during hydrocracking. However, this can result in acolder exit temperature from the hydrocracking reactor. This colder exittemperature may not be sufficient in the dewaxing reactor to achievedesired cold flow properties in the dewaxing reactor.

In a conventional reaction system configuration, the primary method ofcontrolling the temperature of a stage of a reaction system can be basedon passing the feed through a heater prior to having the feed enter theinitial reactor of the stage. In this type of conventionalconfiguration, the use of a single feed heater prior to the firstreactor results in a linkage between the inlet temperature of theinitial reactor, such as a hydrocracking reactor, and the inlettemperature of the second reactor, such as a dewaxing reactor. Somemodification of the link between the hydrocracking inlet temperature andthe dewaxing inlet temperature can be provided by using conventionalcooling or quench streams. However, such quench streams are typicallyonly suitable for cooling an effluent prior to entering the nextreactor. In a situation where it is desirable to perform little or nohydrocracking on a feed for heavy neutral production, but where asufficiently high temperature is needed to perform dewaxing, theconventional solution is to perform hydrocracking at a highertemperature than needed for viscosity index uplift. This results in someyield loss, but provides the necessary input temperature for dewaxing.This loss of yield can be avoided by using hot hydrogen lines asdescribed herein, as use of the hot hydrogen lines can allow for greatervariation between the inlet temperature of the hydrocracking reactor andthe inlet temperature of a subsequent dewaxing reactor.

Additionally or alternately, operating the second stage at a low amountof conversion can potentially lead to reduced aromatic saturation in thehydrocracking reactor of the second stage. In order to maintain thearomatics in the final heavy neutral lubricant product at a desiredlevel, an additional bed of aromatic saturation catalyst can be includedas an initial catalyst bed (or beds) in the dewaxing reactor. This canprovide additional aromatic saturation activity for aspects where theexit temperature of the hydrocracking reactor is colder than the targetinlet temperature of the dewaxing reactor.

When fractionating a feed prior to hydroprocessing for blocked operationand/or fractionating the hydroprocessed effluent from the first stage toform the feeds for blocked operation of the second stage, thefractionation can be performed to produce a feed for light neutral basestock production and a feed for heavy neutral base stock production. The343° C.+ portion of the feed for light neutral base stock production canhave a kinematic viscosity at 100° C. of 1.5 cSt to 6.5 cSt, or 2.0 cStto 6.0 cSt, or 2.0 cSt to 5.0 cSt, or 1.5 cSt to 4.5 cSt. It is notedthat the feed for light neutral base stock production may include somefuels boiling range components (343° C.−), so the kinematic viscosity ofthe full feed to the second stage for light neutral base stockproduction may be lower than the above listed ranges. The feed for heavyneutral base stock production can have a kinematic viscosity at 100° C.of 6.0 cSt or more, or 6.5 cSt or more, or 8.0 cSt or more, such as upto 16 cSt or still higher. It is noted that the feed for heavy neutralbase stock production may correspond to a bottoms fraction, andtherefore may have a viscosity above the typical viscosity for a heavyneutral lubricant base stock. In various aspects, the kinematicviscosity at 100° C. for the feed for heavy neutral base stockproduction can be at least 2.0 cSt higher than the kinematic viscosityat 100° C. for the feed for light neutral base stock production, or atleast 2.5 cSt higher, or at least 3.0 cSt higher, such as up to 6.0 cSthigher or possibly more.

As an example of processing, an initial feedstock can correspond to atypical or conventional feedstock for lubricant base stock production. Afirst processing stage can perform an initial amount of hydrotreatingand/or hydrocracking. A first separation stage can then be used toremove fuels boiling range (and lower boiling range) compounds. Thefirst separation stage can also be used to separate the lubricantboiling range portion of the effluent into a feed for light neutralprocessing and a feed for heavy neutral processing. These separate feedscan be stored, to allow for block operation of the second stage of theprocessing system. During blocked operation of the second stage, thelight neutral feed or heavy neutral feed can be passed into a firstreactor and exposed under hydrocracking conditions to a USY catalystincluding a supported noble metal, such as Pt and/or Pd. The USYcatalyst can have a desirable combination of catalyst properties, suchas a unit cell size of 24.30 or less (or 24.24 or less), a silica toalumina ratio of at least 50 (or at least 80), and an alpha value of 20or less (or 10 or less). The conversion conditions for the heavy neutralfeed can be substantially less severe relative to the conversionconditions for the light neutral feed, as less viscosity index uplift isrequired for the resulting heavy neutral product. The hydrocrackedeffluent can then be passed into a dewaxing reactor. The dewaxingreactor can include both aromatic saturation catalyst and dewaxingcatalyst, with at least a portion of the aromatic saturation catalystbeing upstream from the dewaxing catalyst. During the portion of blockoperation for processing of the heavy neutral feed, the additionalaromatic saturation catalyst in the upstream portion of the reactor canassist with reducing the aromatics content of the heavy neutral feed.The dewaxed effluent can then be passed into a hydrofinishing reactorfor additional aromatic saturation. A final separation can be performedeither on the dewaxed effluent prior to hydrofinishing or on thehydrofinished effluent to separate any additional fuels boiling rangematerial and/or light ends from the desired lubricant base stockproduct.

Optionally, further reductions in aromatics content can be achieved byusing a recycle quench stream. In various aspects, use of a recyclequench stream can allow the effluent from a USY hydrocracking reactor tobe passed into a dewaxing reactor without intermediate separation whilealso allowing for greater relative control of various temperatures. Forexample, the temperature of the hydrocracked effluent at the inlet tothe dewaxing reactor can be at least 10° F. (˜5° C.) cooler than thetemperature of the input feed to the USY hydrocracking reactor, or atleast 20° F. (˜10° C.) cooler, such as up to 40° F. (˜20° C.) cooler ormore. Additionally or alternately, the temperature of the hydrocrackedeffluent at the inlet to the dewaxing reactor can be at least 40° F.(˜20° C.) cooler than the temperature of the hydrocracked effluent atthe exit from the USY hydrocracking reactor, or at least 50° F. (˜25°C.), or at least 60° F. (˜30° C.), such as up to 80° F. (˜40° C.) ormore. In order to cool the hydrocracked effluent, 20 wt % to 50 wt % ofthe dewaxed effluent can be recycled to a location prior to the inlet tothe dewaxing reactor. The location for withdrawing the dewaxed effluentfor recycle can be any convenient location after the dewaxing reactorand prior to fractionation of the dewaxed effluent. For example, if thedewaxing reactor includes a hydrofinishing catalyst and/or if thedewaxed effluent is passed into a separate hydrofinishing reactor priorto fractionation, the dewaxed effluent used for the recycle stream cancorrespond to a recycled portion of a dewaxed and hydrofinishedeffluent. In some aspects, the weight average bed temperature of thedewaxing reactor can be greater than the dewaxing reactor inlettemperature by 15° C. or less, or by 10° C. or less.

FIG. 1 shows an example of a general processing configuration suitablefor block processing of a feedstock to produce multiple lubricant basestock products. In FIG. 1, a hydroprocessed feedstock 105 can beintroduced into a separation stage 160, such as a fractionation tower.The hydroprocessed feedstock 105 can correspond to a “sweet” feedstockwith a sulfur content of 250 wppm or less, or 100 wppm or less, or 50wppm or less. Such a hydroprocessed feedstock can correspond to (atleast a portion of) the hydroprocessed effluent from a first stage of areaction system. The first stage can include one or more hydroprocessingreactors. Examples of suitable types of catalysts for the one or morehydroprocessing reactors can include hydrotreating catalysts,hydrocracking catalysts, and demetallization catalysts. Because thefirst stage is a sour processing stage, the catalysts in the one or morehydroprocessing reactors can typically include base metals. Thehydroprocessed feedstock can be separated by separation stage 160 toform a variety of products. Based on the prior hydroprocessing, thehydroprocessed feedstock may include fuels boiling range compoundsand/or light ends (including C⁴⁻ compounds and/or contaminant gases suchas H₂S). The hydroprocessed feedstock can also include a lubricantboiling range portion. In addition to separating the lubricant boilingrange portion from (a substantial portion of) the fuels boiling rangecompounds, the separation stage 160 can also separate the lubricantboiling range portion into a first lubricant boiling range fraction 162and a second lubricant boiling range fraction 167. The first lubricantboiling range fraction 162 can be stored, for example, in storage tank170, while the second lubricant boiling range fraction 167 can be storedin storage tank 174. This can allow the fractions to be stored until theappropriate time for use, so that the sweet stage of the reaction systemcan be operated in a block processing mode.

During block processing, hydroprocessed feed 175 for input tohydrocracking reactor 110 can correspond either to first lubricantboiling range fraction 172 (from storage tank 170) or second lubricantboiling range fraction 177 (from storage tank 174). The hydroprocessedfeed 175 can be passed into hydrocracking reactor 110 under conditionsthat are selected based on a desired degree of viscosity index uplift inthe resulting hydrocracked effluent 115. For a light neutral feed,higher severity conditions can be selected, such as hydrocrackingconditions with sufficient conversion so that the 343° C.+ portion or a371° C.+ portion of the hydrocracked effluent has a viscosity index of120 or more, or 125 or more, or 130 or more, such as up to 145 orpossibly still higher. For a heavy neutral feed, lower severityconditions can be selected, such as hydrocracking conditions withconversion that results in a hydrocracked effluent with a viscosityindex of 100 or less, or 95 or less, or 90 or less, such as down to 80or possibly still lower. The hydrocracked effluent 115 can optionallyundergo separation to remove lower boiling material, or the hydrocrackedeffluent 115 can be passed into dewaxing reactor 120. In addition todewaxing catalyst, dewaxing reactor 120 can also include an initialportion of aromatic saturation catalyst that is upstream from thedewaxing catalyst. Dewaxing reactor 120 can generate a dewaxed effluent125. Dewaxed effluent 125 can then be passed into hydrofinishing reactor140 for additional aromatic saturation. The hydrofinished effluent 145can then be fractionated 150 to separate the desired lubricant product157 from other portions of the hydrocracked effluent, such as a lightends and/or fuels portion 151, a lighter lubricant product fraction 152,and/or a heavier portion 159 that may have been co-processed with theheavy neutral fraction. Optionally, the dewaxed effluent 125 can befractionated 150 prior to being passed into hydrofinishing reactor 140.

In hydrocracking reactor 110, one or more of the catalyst beds canoptionally contain catalyst different from a hydrocracking catalyst. Forexample, an initial catalyst bed (or portion thereof) and/or a finalcatalyst bed (or portion thereof) in hydrocracking reactor 110 caninclude aromatic saturation catalyst for further reducing the aromaticscontent of a feed. Similarly, an initial catalyst bed (or portionthereof) and/or a final catalyst bed (or portion thereof) in dewaxingreactor 120 can include aromatic saturation catalyst for furtherreducing the aromatics content of a feed

The configuration in FIG. 1 shows details of the configuration relatedto blocked operation. FIG. 2 shows another configuration for the sweetprocessing stage of a reaction system for production of lubricant basestocks. The configuration shown in FIG. 2 provides additional detailsregarding an example of temperature and flow management within areaction system. It is understood that the features shown in FIG. 1 andFIG. 2 can be used separately or in conjunction with each other.

In FIG. 2, a hydroprocessed feed 175 can be passed into a feed heater280 prior to entering hydrocracking reactor 110. Feed heater 280 can beany convenient type of heater that is suitable for heating ofhydrocarbonaceous feeds. In the example shown in FIG. 2, feed heater 280can also include a flow path for heating a portion of ahydrogen-containing stream 101. The feed heater 280 can contribute tocontrol over the inlet temperature for hydrocracking reactor 110 and/ordewaxing reactor 120 based on heating of hydroprocessed feed 175 andheating of a portion of hydrogen-containing stream 101. After heating,the heated hydroprocessed feed 275 can be passed into hydrocrackingreactor 110. Optionally, a portion 278 of the heated hydroprocessed feed275 can be introduced at a downstream location within reactor 110, suchas a location that allows portion 278 to not be exposed to one or morecatalyst beds within reactor 110. With regard to hydrogen-containingstream 101, a heated portion 281 of the hydrogen-containing stream canbe introduced into hydrocracking reactor 110 as part of the feed or as aseparate stream. Similarly, a heated portion 282 of thehydrogen-containing stream can be introduced into dewaxing reactor 120as part of the feed or as a separate stream. In the example shown inFIG. 2, heated portion 281 is mixed with heated hydroprocessed feed 275prior to entering reactor 110, while heated portion 282 is introducedinto reactor 120 directly. It is noted that heated portion 281 andheated portion 282 of the hydrogen-containing stream can be usedselectively. For example, heated portion 281 can be used when a highertemperature is desired in hydrocracking reactor 110, such as duringprocessing of a heated hydroprocessed feed 275 for production of a highviscosity index light neutral base stock. During processing of acorresponding feed for heavy neutral base stock production, heatedportion 281 may be omitted, and non-heated hydrogen 211 may be mixedwith heated hydroprocessed feed 275 instead. Still another option can beto use both heated portion 281 and non-heated hydrogen 211 in a desiredratio. For dewaxing reactor 120, heated portion 282 may be used duringprocessing to form a heavy neutral base stock, as the temperature ofhydrocracking reactor 110 can be lower during the lower conversionprocessing used for heavy neutral production. As a result, hydrocrackedeffluent 115 can have a lower temperature during heavy neutral basestock production, and heated portion 282 of the hydrogen-containingstream can be used to increase the inlet temperature for dewaxingreactor 120. If additional heat is not required (or if less heat isrequired), non-heated hydrogen 221 can be used alone or in combinationwith heated portion 282.

In addition to heater 280 and the associated flows heated by heater 280,it is noted that heat exchangers (not shown) can also be included at anyconvenient location in the configuration in FIG. 2 to further assistwith temperature management.

Further temperature control can be provided by using cooling (or quench)stream 223 and cold hydrogen stream 243. Cooling stream 223 and coldhydrogen stream 243 can allow for control of temperature prior to thefinal catalyst bed(s) in reactors 120 and 140, respectively. In theexample shown in FIG. 2, reactor 120 can include a first bed of aromaticsaturation catalyst, 3 middle beds of dewaxing catalyst, and a final bedof aromatic saturation catalyst. Cooling stream 223 can allow for thefeed in the dewaxing reactor 120 to be exposed to the final aromaticsaturation catalyst at a lower temperature. This can be beneficial forshifting the equilibrium value of aromatics in the feed. Similarly, coldhydrogen stream 243 can allow for the feed in the aromatic saturationreactor 140 to be exposed to the final aromatic saturation catalyst(s)at a lower temperature.

FIG. 3 shows an example of a first stage of a processing system. FIG. 3includes flows for either processing an entire feed 305 or for blockingof a feed 365 in the first stage of the processing system. Forprocessing of a feed 305 without blocking, the feed 305 can beintroduced into a hydroprocessing reactor 390. In FIG. 3, twohydroprocessing reactors 390 and 394 are shown, but it is understoodthat any convenient number of hydroprocessing reactors can be used. Thehydroprocessing reactors can include demetallization catalysts,hydrotreating catalysts, and/or hydrocracking catalysts. In the exampleshown in FIG. 3, the effluent 392 from reactor 390 can be passed into anadditional reactor 394. This can correspond to, for example, having afirst reactor 390 that contains a hydrotreating catalyst and a secondreactor 394 that contains (base metal) hydrocracking catalyst.Optionally, a separation (not shown) could be performed between reactors390 and 394. After the final reactor, such as reactor 394 in FIG. 3, theeffluent 396 from the final reactor can be used a hydroprocessed feed inthe second stage of the reaction system.

If the first stage of the reaction system is operated to perform blockprocessing, a feed 365 can first be introduced into a fractionator 360to generate a light neutral feed fraction 362 and a heavy neutral feedfraction 367. These feed fractions can be stored in storage tanks 380and 384, respectively. Either light neutral feed 382 or heavy neutralfeed 387 can then be used as the input feed 385 to first hydroprocessingreactor 390. The final reactor effluent 396 can correspond to aneffluent that can be passed into an appropriate storage tank (such asstorage 170 or 174), or the effluent can be passed directly into thesecond stage reactors in the reaction system.

FIG. 4 schematically shows another example of a reaction systemincluding a plurality of reactors that can be used, for example, as thesweet stage of a reaction for producing lubricant base stocks. Theconfiguration in FIG. 4 provides an example of a reaction system thatcan independently heat multiple reactors within a reaction system. Thisis in contrast to conventional reaction systems, where typically asingle hydrogen inlet and/or inert gas inlet is used when heating thereaction system. If only a single inlet is used for heating amulti-reactor system, the inlet temperatures for the plurality ofreactors in the multi-reactor system can be linked in a substantialmanner. By contrast, the configuration shown in FIG. 4 can provideadditional flexibility to independently choose inlet temperatures fortwo or more reactors from the plurality of reactors in the multi-reactorsystem.

In FIG. 4, a hydrogen input stream from a hydrogen source 405 is passedthrough valve 406 into a heater 410. In the configuration shown in FIG.4, hydrogen input stream 405 and feed 401 are shown as being combinedprior to entering the heater to form a single heated output stream 414.In other aspects, multiple heated output streams 414 can be used, suchas a first heated output stream containing heated hydrogen and a secondheated output stream containing heated feed. More generally, it isunderstood that any convenient number of input and/or output streams canbe used in conjunction with one or more heaters 410 for forming heatedfeed streams and heated hydrogen stream. It is noted that valves 406 and402 can be used to control when hydrogen 405 and feed 401, respectively,are passed through heater 410 to form heated output stream 414. Forexample, as shown in FIG. 4, if valve 406 is open and valve 402 isclosed, then heated output stream 414 can correspond to a heatedhydrogen stream.

The heated hydrogen in heated output stream 414 can be used for avariety of purposes. When desired, heated hydrogen from heated outputstream 414 can be passed into first reactor 420. Additionally, secondheated hydrogen stream 431 and third heated hydrogen stream 441 can beoptionally introduced into the second reactor 430 and third reactor 440,respectively. These optional hydrogen streams can be introduced at anyconvenient time. Thus, the optional hydrogen lines can be used prior tofeed processing, such as during catalyst activation; during feedprocessing, such as to facilitate independent control over temperaturesin the reactors in a reaction system; or after feed processing, such asfor regeneration of a catalyst. In FIG. 4, reactors 420, 430, and 440can represent any convenient type of reactors suitable for processing afeed in the presence of hydrogen and a catalyst. The catalysts inreactors 420, 430, and 440 can be the same or different. Optionally, atleast one of reactors 420, 430, and 440 can contain a noble metalcatalyst having a highly siliceous support. More generally, anyconvenient number of reactors can be present, such as a plurality ofreactors.

During operation of the reactors for processing of a feed, feed 401 andhydrogen 405 from heated output 414 can be introduced into reactor 420.The hydroprocessing in reactor 420 can result in a hydroprocessedeffluent 425. Optionally, at least a portion of the hydroprocessedeffluent 425 can be passed through a heat exchanger 426 and/or anotherheating or cooling device for adjustment of the temperature ofhydroprocessed effluent 425. The hydroprocessed effluent 425, afteroptional temperature adjustment, can then be passed into reactor 430.The hydroprocessing in reactor 430 can result in a second hydroprocessedeffluent 435. Optionally, at least a portion of the secondhydroprocessed effluent 435 can be passed through a heat exchanger 436and/or another heating or cooling device for adjustment of thetemperature of the second hydroprocessed effluent 435. The secondhydroprocessed effluent 435, after optional temperature adjustment, canthen be passed into reactor 440 for processing to form thirdhydroprocessed effluent 445. After optional temperature adjustment 446,the third hydroprocessed effluent 445 can be further processed,fractionated, stored in drums, or disposed of/used in any convenientmanner.

It is noted that the additional heated hydrogen lines, represented byheated hydrogen lines 431 and 441 in FIG. 4, can enable other types ofprocessing within a reaction system in addition to catalyst activation.As an example, a hypothetical system could include noble metal catalystsin both reactor 430 and reactor 440, such as a noble metal dewaxingcatalyst in reactor 430 and a noble metal hydrofinishing catalyst inreactor 440. For such a reaction system, process “upsets” can occur fromtime to time, where an undesirable feed and/or a less than fullprocessed feed may be able to enter downstream reactors, such asreactors 430 and 440. When such a process upset occurs, the undesirablefeed may contaminate the catalyst beds in the reactors, and this maycause catalyst deactivation and/or poisoning. In order to restorecatalyst activity, it may be desirable to expose the catalysts in thereaction system to a cleaning feed at an elevated temperature. However,if the only heat source available is the heater for the feed into theinitial stage, as the cleaning feed passes through the reactors, thefeed will lose temperature and can be substantially cooler by the timethe feed reaches the final reactor in a reaction system. One optioncould be to increase the cleaning feed temperature into the initialreactor, but temperatures above roughly 385° C. could lead to thermalcracking and coking in the presence of a catalyst, which can placeeffective limits on the temperature in the final reactor(s). Havingindependent heated hydrogen lines can assist with achieving highertemperatures during a regeneration or cleaning cycle without having torisk catalyst coking in earlier reactors.

It is noted that the configurations shown in FIGS. 1-4 provide variousexamples of process elements (reactors, fractionators, heaters, etc.)that are in fluid communication with one another. Process elements canbe in direct fluid communication or indirect fluid communication withanother process element. For example, in FIG. 2 the outlet ofhydrocracking reactor 110 is shown as being in direct fluidcommunication with the inlet of dewaxing reactor 120. The outlet ofhydrocracking reactor 110 is in indirect fluid communication withhydrofinishing reactor 140, based on the intervening presence ofdewaxing reactor 120. It is noted that process elements that do notalter the composition of a flow, such as a heat exchanger, may beincluded within a direct fluid communication flow path.

In this discussion, reference may be made to operating a reactor atsubstantially similar conditions during different phases of blockedoperation. For example, during blocked operation of the second stage ofa reaction system, the conditions for hydrocracking may differsubstantially for light neutral base stock production and heavy neutralbase stock production, while the conditions for the dewaxing reactor andthe hydrofinishing reactor are substantially similar for production ofboth types of base stocks. In this discussion, substantially similarconditions for operating a reactor are defined as processing conditionswhere the temperature, pressure, LHSV, and hydrogen treat gas ratediffer by less than specified relative amounts between processing of thefeed types. Substantially similar conditions for a reactor are definedas a) an inlet temperature that differs by 10° C. or less between lightneutral and heavy neutral processing; b) an exit temperature thatdiffers by 10° C. or less between light neutral and heavy neutralprocessing; c) an inlet pressure that differs by less than 5% of thehighest pressure value between light neutral and heavy neutralprocessing; d) a LHSV that differs by 0.12 hr⁻¹ or less between lightneutral and heavy neutral processing; and e) a hydrogen treat gas ratethat differs by less than 10% of the highest treat gas rate betweenlight neutral and heavy neutral processing. It is noted that for thehydrogen treat gas rate, the difference between the rates is calculatedbased on the rate of hydrogen flow only. If inerts (such as nitrogen)are present in the treat gas, only the percentage of the flowcorresponding to hydrogen should be considered.

In this discussion, the naphtha boiling range is defined as 50° F. (˜10°C., roughly corresponding to the lowest boiling point of a pentaneisomer) to 315° F. (157° C.). The jet boiling range is defined as 315°F. (157° C.) to 460° F. (238° C.). The diesel boiling range is definedas 460° F. (238° C.) to 650° F. (343° C.). The distillate fuel boilingrange (jet plus diesel), is defined as 315° F. (157° C.) to 650° F.(343° C.). The fuels boiling range is defined as ˜10° C. to 343° C. Thelubricant boiling range is defined as 650° F. (343° C.) to 1050° F.(566° C.). Optionally, when forming a lubricant boiling portion byfractionation after one or more stages of hydroprocessing (e.g.,hydrotreating, hydrocracking, catalytic dewaxing, hydrofinishing), alubricant boiling range portion can optionally correspond to a bottomsfraction, so that higher boiling range compounds may also be included inthe lubricant boiling range portion. Compounds (C⁴⁻) with a boilingpoint below the naphtha boiling range can be referred to as light ends.It is noted that due to practical consideration during fractionation (orother boiling point based separation) of hydrocarbon-like fractions, afuel fraction formed according to the methods described herein may haveT5 and T95 distillation points corresponding to the above values (or T10and T90 distillation points), as opposed to having initial/final boilingpoints corresponding to the above values.

In this discussion, unless otherwise specified, references to a liquideffluent or a liquid product are references to an effluent or productthat is a liquid at 25° C. and 100 kPa-a (˜1 atm).

In this discussion, conditions may be provided for various types ofhydroprocessing of feeds or effluents. Examples of hydroprocessing caninclude, but are not limited to, one or more of hydrotreating,demetallization, hydrocracking, catalytic dewaxing, andhydrofinishing/aromatic saturation. Such hydroprocessing conditions canbe controlled to have desired values for the conditions (e.g.,temperature, pressure, LHSV, treat gas rate) by using at least onecontroller, such as a plurality of controllers, to control one or moreof the hydroprocessing conditions. In some aspects, for a given type ofhydroprocessing, at least one controller can be associated with eachtype of hydroprocessing condition. In some aspects, one or more of thehydroprocessing conditions can be controlled by an associatedcontroller. Examples of structures that can be controlled by acontroller can include, but are not limited to, valves that control aflow rate, a pressure, or a combination thereof; heat exchangers and/orheaters that control a temperature; and one or more flow meters and oneor more associated valves that control relative flow rates of at leasttwo flows. Such controllers can optionally include a controller feedbackloop including at least a processor, a detector for detecting a value ofa control variable (e.g., temperature, pressure, flow rate, and aprocessor output for controlling the value of a manipulated variable(e.g., changing the position of a valve, increasing or decreasing theduty cycle and/or temperature for a heater). Optionally, at least onehydroprocessing condition for a given type of hydroprocessing may nothave an associated controller.

Group I basestocks or base oils are defined as base oils with less than90 wt % saturated molecules and/or at least 0.03 wt % sulfur content.Group I basestocks also have a viscosity index (VI) of at least 80 butless than 120. Group II basestocks or base oils contain at least 90 wt %saturated molecules and less than 0.03 wt % sulfur. Group II basestocksalso have a viscosity index of at least 80 but less than 120. Group IIIbasestocks or base oils contain at least 90 wt % saturated molecules andless than 0.03 wt % sulfur, with a viscosity index of at least 120. Inaddition to the above formal definitions, some Group I basestocks may bereferred to as a Group I+ basestock, which corresponds to a Group Ibasestock with a VI value of 103 to 108. Some Group II basestocks may bereferred to as a Group II+ basestock, which corresponds to a Group IIbasestock with a VI of at least 113. Some Group III basestocks may bereferred to as a Group III+ basestock, which corresponds to a Group IIIbasestock with a VI value of at least 140.

Feedstocks

A wide range of petroleum and chemical feedstocks can be hydroprocessedin accordance with the invention. Suitable feedstocks include whole andreduced petroleum crudes, atmospheric, cycle oils, gas oils, includingvacuum gas oils and coker gas oils, light to heavy distillates includingraw virgin distillates, hydrocrackates, hydrotreated oils, slack waxes,Fischer-Tropsch waxes, raffinates, deasphalted oils, and mixtures ofthese materials.

As noted above, the feedstock can optionally include desaphalted oil. Insome aspects, a deasphalted oil can correspond to a low lift deasphaltedoil, such as a deasphalted oil formed by deasphalting a vacuum residboiling range feed (T10 distillation point of 510° C. or more) toproduce a yield of deasphalted oil of roughly 40 wt % or less, or 35 wt% or less, or 30 wt % or less, such as down to 20 wt % or possibly stilllower. This can correspond to, for example, a deasphalted oil formed byconventional propane deasphalting of a vacuum resid boiling range feed.In other aspects, a deasphalted oil can correspond to a high liftdeasphalted oil, such as a deasphalted oil formed by deasphalting avacuum resid boiling range feed (T10 distillation point of 510° C. ormore) to produce a yield of deasphalted oil of at least 50 wt %, or atleast 60 wt %, or at least 65 wt %, or at least 70 wt % such as up to 80wt % or possibly still higher. This can correspond to, for example, adeasphalted oil formed by deasphalting using a C₄₊ solvent or a C₅₊solvent. A C_(n+) solvent is defined as a hydrocarbon solvent thatincludes at least 50 wt % of alkanes that contain “n” carbons or more,or at least 75 wt %, such as up to the solvent being substantiallycompletely composed of alkanes that contain “n” carbons or more. Butaneis an example of a C₄ solvent. Pentane, hexane, and heptane are examplesof C₅₊ solvents. It is noted that alkanes can include n-alkanes andbranched alkanes.

One way of defining a feedstock is based on the boiling range of thefeed. One option for defining a boiling range is to use an initialboiling point for a feed and/or a final boiling point for a feed.Another option is to characterize a feed based on the amount of the feedthat boils at one or more temperatures. For example, a “T5” boilingpoint/distillation point for a feed is defined as the temperature atwhich 5 wt % of the feed will boil off. Similarly, a “T95” boilingpoint/distillation point is a temperature at 95 wt % of the feed willboil. Boiling points, including fractional weight boiling points, can bedetermined using a suitable ASTM method, such as ASTM D2887.

Typical feeds include, for example, feeds with an initial boiling pointand/or a T5 boiling point and/or T10 boiling point of at least 600° F.(˜316° C.), or at least 650° F. (˜343° C.), or at least 700° F. (371°C.), or at least 750° F. (˜399° C.). Additionally or alternately, thefinal boiling point and/or T95 boiling point and/or T90 boiling point ofthe feed can be 1100° F. (˜593° C.) or less, or 1050° F. (˜566° C.) orless, or 1000° F. (˜538° C.) or less, or 950° F. (˜510° C.) or less. Inparticular, a feed can have a T5 to T95 boiling range of 600° F. (˜316°C.) to 1100° F. (˜593° C.), or a T5 to T95 boiling range of 650° F.(˜343° C.) to 1050° F. (˜566° C.), or a T10 to T90 boiling range of 650°F. (˜343° C.) to 1050° F. (˜566° C.) Optionally, if the hydroprocessingis also used to form fuels, it can be possible to use a feed thatincludes a lower boiling range portion. Such a feed can have an initialboiling point and/or a T5 boiling point and/or T10 boiling point of atleast 350° F. (˜177° C.), or at least 400° F. (˜204° C.), or at least450° F. (˜232° C.). In particular, such a feed can have a T5 to T95boiling range of 350° F. (˜177° C.) to 1100° F. (˜593° C.), or a T5 toT95 boiling range of 450° F. (˜232° C.) to 1050° F. (˜566° C.), or a T10to T90 boiling range of 350° F. (˜177° C.) to 1050° F. (˜566° C.).

In some aspects, the aromatics content of the feed can be at least 20 wt%, or at least 30 wt %, or at least 40 wt %, or at least 50 wt %, or atleast 60 wt %. In particular, the aromatics content can be 20 wt % to 90wt %, or 40 wt % to 80 wt %, or 50 wt % to 80 wt %.

In aspects where the hydroprocessing includes a hydrotreatment processand/or a sour hydrocracking process, the feed can have a sulfur contentof 500 wppm to 20000 wppm or more, or 500 wppm to 10000 wppm, or 500wppm to 5000 wppm. Additionally or alternately, the nitrogen content ofsuch a feed can be 20 wppm to 4000 wppm, or 50 wppm to 2000 wppm. Insome aspects, the feed can correspond to a “sweet” feed, so that thesulfur content of the feed is 10 wppm to 500 wppm and/or the nitrogencontent is 1 wppm to 100 wppm.

In some embodiments, at least a portion of the feed can correspond to afeed derived from a biocomponent source. In this discussion, abiocomponent feedstock refers to a hydrocarbon feedstock derived from abiological raw material component, from biocomponent sources such asvegetable, animal, fish, and/or algae. Note that, for the purposes ofthis document, vegetable fats/oils refer generally to any plant basedmaterial, and can include fat/oils derived from a source such as plantsof the genus Jatropha. Generally, the biocomponent sources can includevegetable fats/oils, animal fats/oils, fish oils, pyrolysis oils, andalgae lipids/oils, as well as components of such materials, and in someembodiments can specifically include one or more type of lipidcompounds. Lipid compounds are typically biological compounds that areinsoluble in water, but soluble in nonpolar (or fat) solvents.Non-limiting examples of such solvents include alcohols, ethers,chloroform, alkyl acetates, benzene, and combinations thereof.

Second Stage Hydrocracking

In various aspects, the second stage for processing a feedstock caninclude exposing at least a portion of the feedstock to a hydrocrackingcatalyst under hydrocracking conditions. The exposure to a hydrocrackingcatalyst can occur in the first reactor(s) of a plurality of reactors inthe second stage, with the second stage hydrocracked effluentsubsequently be exposed to catalyst in one or more additional reactors,such as a reactor including dewaxing catalyst and/or a reactor includinghydrofinishing catalyst.

Hydrocracking catalysts typically contain sulfided base metals on acidicsupports, such as amorphous silica alumina; cracking zeolites such asUSY, zeolite Beta, or ZSM-5; or acidified alumina. Often these acidicsupports are mixed or bound with other metal oxides such as alumina,titania or silica. Non-limiting examples of metals for hydrocrackingcatalysts include nickel, nickel-cobalt-molybdenum, cobalt-molybdenum,nickel-tungsten, nickel-molybdenum, and/or nickel-molybdenum-tungsten.Additionally or alternately, hydrocracking catalysts with noble metalscan also be used. Non-limiting examples of noble metal catalysts includethose based on platinum and/or palladium. Support materials which may beused for both the noble and non-noble metal catalysts can comprise arefractory oxide material such as alumina, silica, alumina-silica,kieselguhr, diatomaceous earth, magnesia, zirconia, or combinationsthereof, with alumina, silica, alumina-silica being the most common (andpreferred, in one embodiment).

In aspects where a hydrocracking catalyst includes Group VIII noblemetals, such as for hydrocracking in a “sweet” hydrocracking stage, theone or more Group VIII metals can be present in an amount ranging from0.1 wt % to 5.0 wt %, or 0.1 wt % to 2.0 wt %, or 0.3 wt % to 2.0 wt %,or 0.1 wt % to 1.5 wt %, or 0.3 wt % to 1.5 wt %. In aspects where ahydrocracking catalyst includes base metals, the at least one Group VIIInon-noble metal, in oxide form, can typically be present in an amountranging from 2 wt % to 40 wt %, preferably from 4 wt % to 15 wt %. Theat least one Group VIB metal, in oxide form, can typically be present inan amount ranging from 2 wt % to 70 wt %, preferably for supportedcatalysts from 6 wt % to 40 wt % or from 10 wt % to 30 wt %. Theseweight percents are based on the total weight of the catalyst. In someaspects, suitable hydrocracking catalysts can include nickel/molybdenum,nickel/tungsten, or nickel/molybdenum/tungsten as metals supported onthe hydrocracking catalyst.

In some aspects, a hydrocracking catalyst can include a large poremolecular sieve that is selective for cracking of branched hydrocarbonsand/or cyclic hydrocarbons. Zeolite Y, such as Ultrastable zeolite Y(USY) is an example of a zeolite molecular sieve that is selective forcracking of branched hydrocarbons and cyclic hydrocarbons. Depending onthe aspect, the silica to alumina ratio in a USY zeolite can be at least10, such as at least 15, or at least 25, or at least 50, or at least100. Depending on the aspect, the unit cell size for a USY zeolite canbe 24.50 Angstroms or less, such as 24.45 Angstroms or less, or 24.40Angstroms or less, or 24.35 Angstroms or less, such as 24.30 Angstroms(or less). In other aspects, a variety of other types of molecularsieves can be used in a hydrocracking catalyst, such as zeolite Beta andZSM-5. Still other types of suitable molecular sieves can includemolecular sieves having 10-member ring pore channels or 12-member ringpore channels. Examples of molecular sieves having 10-member ring porechannels or 12-member ring pore channels include molecular sieves havingzeolite framework structures selected from MRE, MTT, EUO, AEL, AFO, SFF,STF, TON, OSI, ATO, GON, MTW, SFE, SSY, or VET.

In some aspects, the second stage for processing of a feedstock cancorrespond to exposing at least a portion of the feedstock to a USYcatalyst with a desirable combination of properties. The properties canbe measured prior to the addition of loaded metals on the catalyst. TheUSY catalyst can have a unit cell size of 24.30 Å or less, or 24.27 Å orless, or 24.24 Å or less. Additionally or alternately, the USY catalystcan have a silica to alumina ratio of at least 50, or at least 70, or atleast 90, or at least 100, or at least 110, or at least 120, or at least125, and optionally up to 250 or more, or not more than 1000. This levelof silica to alumina ratio can correspond to a “dealuminated” version ofthe catalyst. Additionally or alternately, the USY catalyst can have analpha value of 20 or less, or 10 or less. The alpha value test is ameasure of the cracking activity of a catalyst and is described in U.S.Pat. No. 3,354,078 and in the Journal of Catalysis, Vol. 4, p. 527(1965); Vol. 6, p. 278 (1966); and Vol. 61, p. 395 (1980), eachincorporated herein by reference as to that description. Theexperimental conditions of the test used herein include a constanttemperature of 538° C. and a variable flow rate as described in detailin the Journal of Catalysis, Vol. 61, p. 395.

A USY hydrocracking catalyst can also include a binder material.Suitable binder materials include materials selected from metal oxides,zeolites, aluminum phosphates, polymers, carbons, and clays. Mostpreferable, the binder is comprised of at least one metal oxide,preferably selected from silica, alumina, silica-alumina, amorphousaluminosilicates, boron, titania, and zirconia. Preferably, the binderis selected from silica, alumina, and silica-alumina. In a preferredembodiment, the binder is comprised of pseudoboehmite alumina.

A catalyst can contain from 0 to 99 wt % binder materials, or 25 to 80wt %, or 35 to 75 wt %, or 50 to 65 wt % of the overall finalhydrocracking catalyst. In other preferred embodiments, a hydrocrackingcatalyst can be less than 80 wt % binder materials, or less than 75 wt%, or less than 65 wt %, or less than 50 wt %.

A hydrocracking catalyst containing USY zeolite may also containadditional zeolites or molecular sieves. In some aspects, ahydrocracking catalyst can further comprise at least one of thefollowing molecular sieves: beta, ZSM-5, ZSM-11, ZSM-57, MCM-22, MCM-49,MCM-56, ITQ-7, ITQ-27, ZSM-48, mordenite, zeolite L, ferrierite, ZSM-23MCM-68, SSZ-26/-33, SAPO-37, ZSM-12, ZSM-18, and EMT faujasites. In suchaspects, the hydrocracking catalyst can contain the EMY zeolite in anamount of at least 10 wt %, more preferably at least at least 25 wt %,and even more preferably at least 35 wt % or even at least 50 wt % basedon the finished catalyst, particularly when a binder is utilized.

A USY hydrocracking catalyst can also include at least one hydrogenatingmetal component supported on the catalyst. Examples of suchhydrogenating metal components can include one or more noble metals fromGroups 8-10 of the IUPAC periodic table. Optionally but preferably, thehydrocracking catalyst can include at least one Group 8/9/10 metalselected from Pt, Pd, Rh and Ru (noble metals), or combinations thereof.In an aspect, the hydrocracking catalyst can comprise at least one Group8/9/10 metal selected from Pt, Pd, or a combination thereof. In anaspect, the hydrocracking catalyst can comprise Pt. The at least onehydrogenating metal may be incorporated into the catalyst by anytechnique known in the art. A preferred technique for active metalincorporation into the catalyst herein is the incipient wetnesstechnique.

The amount of active metal in the catalyst can be at least 0.1 wt %based on catalyst, or at least 0.15 wt %, or at least 0.2 wt %, or atleast 0.25 wt %, or at least 0.3 wt %, or at least 0.5 wt % based on thecatalyst. For embodiments where the Group 8/9/10 metal is Pt, Pd, Rh,Ru, or a combination thereof, the amount of active metal is preferablyfrom 0.1 to 5 wt %, more preferably from 0.2 to 4 wt %, and even morepreferably from 0.25 to 3.5 wt %.

Hydrocracking conditions in the second stage (under “sweet” conditionswith a sulfur content of 250 wppm or less, or 100 wppm or less) caninclude a temperature of from 200 to 450° C., preferably 270 to 400° C.,a hydrogen partial pressure of from 1.8 to 34.6 MPag (˜250 to ˜5000psi), preferably 4.8 to 20.8 MPag, a liquid hourly space velocity offrom 0.2 to 10 hr⁻¹, preferably 0.5 to 3.0 hr⁻¹, and a hydrogencirculation rate of from 35.6 to 1781 m³/m³ (˜200 to ˜10,000 SCF/B),preferably 178 to 890.6 m³/m³ (˜1000 to ˜5000 scf/B). Additionally oralternately, the conditions can include temperatures in the range of600° F. (˜343° C.) to 815° F. (˜435° C.), hydrogen partial pressures offrom 500 psig to 3000 psig (˜3.5 MPag to ˜20.9 MPag), and hydrogen treatgas rates of from 213 m³/m³ to 1068 m³/m³ (˜1200 SCF/B to ˜6000 SCF/B).

Examples of suitable zeolite Y catalysts for the processes describedherein can include catalysts based on aggregated Y zeolite (or Meso-Y)and Extra Mesoporous Y (“EMY”) zeolite. Additional description ofaggregated Y zeolite (Meso-Y) can be found in U.S. Pat. No. 8,778,171,which is incorporated herein by reference with regard to description ofaggregated Y zeolite and methods for making a catalyst containingaggregated Y zeolite. Additional description of Extra Mesoporous Yzeolite can be found in U.S. Pat. No. 8,932,454, which is incorporatedherein by reference with regard to description of EMY zeolite andmethods for making a catalyst containing EMY zeolite.

First Hydroprocessing Stage—Hydrotreating and/or Hydrocracking

In various aspects, a first hydroprocessing stage can be used to improveone or more qualities of a feedstock for lubricant base oil production.Examples of improvements of a feedstock can include, but are not limitedto, reducing the heteroatom content of a feed, performing conversion ona feed to provide viscosity index uplift, and/or performing aromaticsaturation on a feed.

With regard to heteroatom removal, the conditions in the initialhydroprocessing stage (hydrotreating and/or hydrocracking) can besufficient to reduce the sulfur content of the hydroprocessed effluentto 250 wppm or less, or 200 wppm or less, or 150 wppm or less, or 100wppm or less, or 50 wppm or less, or 25 wppm or less, or 10 wppm orless. In particular, the sulfur content of the hydroprocessed effluentcan be 1 wppm to 250 wppm, or 1 wppm to 50 wppm, or 1 wppm to 10 wppm.Additionally or alternately, the conditions in the initialhydroprocessing stage can be sufficient to reduce the nitrogen contentto 100 wppm or less, or 50 wppm or less, or 25 wppm or less, or 10 wppmor less. In particular, the nitrogen content can be 1 wppm to 100 wppm,or 1 wppm to 25 wppm, or 1 wppm to 10 wppm.

In aspects that include hydrotreating as part of the initialhydroprocessing stage, the hydrotreating catalyst can comprise anysuitable hydrotreating catalyst, e.g., a catalyst comprising at leastone Group 8-10 non-noble metal (for example selected from Ni, Co, and acombination thereof) and at least one Group 6 metal (for exampleselected from Mo, W, and a combination thereof), optionally including asuitable support and/or filler material (e.g., comprising alumina,silica, titania, zirconia, or a combination thereof). The hydrotreatingcatalyst according to aspects of this invention can be a bulk catalystor a supported catalyst. Techniques for producing supported catalystsare well known in the art. Techniques for producing bulk metal catalystparticles are known and have been previously described, for example inU.S. Pat. No. 6,162,350, which is hereby incorporated by reference. Bulkmetal catalyst particles can be made via methods where all of the metalcatalyst precursors are in solution, or via methods where at least oneof the precursors is in at least partly in solid form, optionally butpreferably while at least another one of the precursors is provided onlyin a solution form. Providing a metal precursor at least partly in solidform can be achieved, for example, by providing a solution of the metalprecursor that also includes solid and/or precipitated metal in thesolution, such as in the form of suspended particles. By way ofillustration, some examples of suitable hydrotreating catalysts aredescribed in one or more of U.S. Pat. Nos. 6,156,695, 6,162,350,6,299,760, 6,582,590, 6,712,955, 6,783,663, 6,863,803, 6,929,738,7,229,548, 7,288,182, 7,410,924, and 7,544,632, U.S. Patent ApplicationPublication Nos. 2005/0277545, 2006/0060502, 2007/0084754, and2008/0132407, and International Publication Nos. WO 04/007646, WO2007/084437, WO 2007/084438, WO 2007/084439, and WO 2007/084471, interalia. Preferred metal catalysts include cobalt/molybdenum (1-10% Co asoxide, 10-40% Mo as oxide), nickel/molybdenum (1-10% Ni as oxide, 10-40%Co as oxide), or nickel/tungsten (1-10% Ni as oxide, 10-40% W as oxide)on alumina.

In various aspects, hydrotreating conditions can include temperatures of200° C. to 450° C., or 315° C. to 425° C.; pressures of 250 psig (˜1.8MPag) to 5000 psig (˜34.6 MPag) or 500 psig (˜3.4 MPag) to 3000 psig(˜20.8 MPag), or 800 psig (˜5.5 MPag) to 2500 psig (˜17.2 MPag); LiquidHourly Space Velocities (LHSV) of 0.2-10 h⁻¹; and hydrogen treat ratesof 200 scf/B (35.6 m³/m³) to 10,000 scf/B (1781 m³/m³), or 500 (89m³/m³) to 10,000 scf/B (1781 m³/m³).

Hydrotreating catalysts are typically those containing Group 6 metals,and non-noble Group 8-10 metals, i.e., iron, cobalt and nickel andmixtures thereof. These metals or mixtures of metals are typicallypresent as oxides or sulfides on refractory metal oxide supports.Suitable metal oxide supports include low acidic oxides such as silica,alumina or titania, preferably alumina. In some aspects, preferredaluminas can correspond to porous aluminas such as gamma or eta havingaverage pore sizes from 50 to 200 Å, or 75 to 150 Å; a surface area from100 to 300 m²/g, or 150 to 250 m²/g; and/or a pore volume of from 0.25to 1.0 cm³/g, or 0.35 to 0.8 cm³/g. The supports are preferably notpromoted with a halogen such as fluorine as this generally increases theacidity of the support.

Alternatively, the hydrotreating catalyst can be a bulk metal catalyst,or a combination of stacked beds of supported and bulk metal catalyst.By bulk metal, it is meant that the catalysts are unsupported whereinthe bulk catalyst particles comprise 30-100 wt. % of at least one Group8-10 non-noble metal and at least one Group 6 metal, based on the totalweight of the bulk catalyst particles, calculated as metal oxides andwherein the bulk catalyst particles have a surface area of at least 10m²/g. It is furthermore preferred that the bulk metal hydrotreatingcatalysts used herein comprise 50 to 100 wt %, and even more preferably70 to 100 wt %, of at least one Group 8-10 non-noble metal and at leastone Group 6 metal, based on the total weight of the particles,calculated as metal oxides. The amount of Group 6 and Group 8-10non-noble metals can easily be determined VIB TEM-EDX.

Bulk catalyst compositions comprising one Group 8-10 non-noble metal andtwo Group 6 metals are preferred. It has been found that in this case,the bulk catalyst particles are sintering-resistant. Thus the activesurface area of the bulk catalyst particles is maintained during use.The molar ratio of Group 6 to Group 8-10 non-noble metals rangesgenerally from 10:1-1:10 and preferably from 3:1-1:3, In the case of acore-shell structured particle, these ratios of course apply to themetals contained in the shell. If more than one Group 6 metal iscontained in the bulk catalyst particles, the ratio of the differentGroup 6 metals is generally not critical. The same holds when more thanone Group 8-10 non-noble metal is applied. In the case where molybdenumand tungsten are present as Group 6 metals, the molybenum:tungsten ratiopreferably lies in the range of 9:1-1:9. Preferably the Group 8-10non-noble metal comprises nickel and/or cobalt. It is further preferredthat the Group 6 metal comprises a combination of molybdenum andtungsten. Preferably, combinations of nickel/molybdenum/tungsten andcobalt/molybdenum/tungsten and nickel/cobalt/molybdenum/tungsten areused. These types of precipitates appear to be sinter-resistant. Thus,the active surface area of the precipitate is maintained during use. Themetals are preferably present as oxidic compounds of the correspondingmetals, or if the catalyst composition has been sulfided, sulfidiccompounds of the corresponding metals.

In some optional aspects, the bulk metal hydrotreating catalysts usedherein have a surface area of at least 50 m²/g and more preferably of atleast 100 m²/g. In such aspects, it is also desired that the pore sizedistribution of the bulk metal hydrotreating catalysts be approximatelythe same as the one of conventional hydrotreating catalysts. Bulk metalhydrotreating catalysts can have a pore volume of 0.05-5 ml/g, or of0.1-4 ml/g, or of 0.1-3 ml/g, or of 0.1-2 tag determined by nitrogenadsorption. Preferably, pores smaller than 1 nm are not present. Thebulk metal hydrotreating catalysts can have a median diameter of atleast 50 nm, or at least 100 nm. The bulk metal hydrotreating catalystscan have a median diameter of not more than 5000 μm, or not more than3000 μm. In an embodiment, the median particle diameter lies in therange of 0.1-50 μm and most preferably in the range of 0.5-50 μm.

In aspects that include hydrocracking as part of the initialhydroprocessing stage, the initial stage hydrocracking catalyst cancomprise any suitable or standard hydrocracking catalyst, for example, azeolitic base selected from zeolite Beta, zeolite X, zeolite Y,faujasite, ultrastable Y (USY), dealuminized Y (Deal Y), Mordenite,ZSM-3, ZSM-4, ZSM-18, ZSM-20, ZSM-48, and combinations thereof, whichzeolitic base can advantageously be loaded with one or more activemetals (e.g., either (i) a Group 8-10 noble metal such as platinumand/or palladium or (ii) a Group 8-10 non-noble metal such nickel,cobalt, iron, and combinations thereof, and a Group 6 metal such asmolybdenum and/or tungsten). In this discussion, zeolitic materials aredefined to include materials having a recognized zeolite frameworkstructure, such as framework structures recognized by the InternationalZeolite Association. Such zeolitic materials can correspond tosilicoaluminates, silicoaluminophosphates, aluminophosphates, and/orother combinations of atoms that can be used to form a zeoliticframework structure. In addition to zeolitic materials, other types ofcrystalline acidic support materials may also be suitable. Optionally, azeolitic material and/or other crystalline acidic material may be mixedor bound with other metal oxides such as alumina, titania, and/orsilica.

A hydrocracking process in the first stage (or otherwise under sourconditions) can be carried out at temperatures of 200° C. to 450° C.,hydrogen partial pressures of from 250 psig to 5000 psig (˜1.8 MPag to˜34.6 MPag), liquid hourly space velocities of from 0.2 h⁻¹ to 10 h⁻¹,and hydrogen treat gas rates of from 35.6 m³/m³ to 1781 m³/m³ (˜200SCF/B to ˜10,000 SCF/B), Typically, in most cases, the conditions caninclude temperatures in the range of 300° C. to 450° C., hydrogenpartial pressures of from 500 psig to 2000 psig (˜3.5 MPag to ˜13.9MPag), liquid hourly space velocities of from 0.3 h⁻¹ to 2 h⁻¹ andhydrogen treat gas rates of from 213 m³/m³ to 1068 m³/m³ (˜1200 SCF/B to˜6000 SCF/B).

Optionally, a demetallization catalyst can be included as part of theinitial processing stage. Conventional catalysts and conditions fordemetallization can be used. In some aspects, an initial bed ofdemetallization catalyst can be included in a hydrotreating reactor, sothat demetallization is performed under hydrotreating conditions.

Additional Second Stage Processing—Dewaxing and Hydrofinishing/AromaticSaturation

After hydroprocessing in the first stage, the hydroprocessed effluentcan be separated. In some aspects the separation can correspond to aseparation that is primarily focused on separation of contaminant gases(H₂S, NH₃) that are generated during heteroatom removal. In someaspects, additional lower boiling portions of the hydroprocessedeffluent can be separated out, such as naphtha and/or diesel boilingrange portions. In such aspects, a lubricant boiling range portion(optionally including a diesel boiling range portion and/or otherhydroprocessed bottoms) can be further processed by catalytic dewaxingand/or hydrofinishing or aromatic saturation.

In various aspects, catalytic dewaxing can be included as part of asecond or subsequent processing stage. Preferably, the dewaxingcatalysts are zeolites (and/or zeolitic crystals) that perform dewaxingprimarily by isomerizing a hydrocarbon feedstock. More preferably, thecatalysts are zeolites with a unidimensional pore structure. Suitablecatalysts include 10-member ring pore zeolites, such as EU-1, ZSM-35 (orferrierite), ZSM-11, ZSM-57, NU-87, SAPO-11, and ZSM-22. Preferredmaterials are EU-2, EU-11, ZBM-30, ZSM-48, or ZSM-23. ZSM-48 is mostpreferred. Note that a zeolite having the ZSM-23 structure with a silicato alumina ratio of from 20:1 to 40:1 can sometimes be referred to asSSZ-32. Other zeolitic crystals that are isostructural with the abovematerials include Theta-1, NU-10, EU-13, KZ-1, and NU-23.

In various embodiments, the dewaxing catalysts can further include ametal hydrogenation component. The metal hydrogenation component istypically a Group 6 and/or a Group 8-10 metal. Preferably, the metalhydrogenation component is a Group 8-10 noble metal. Preferably, themetal hydrogenation component is Pt, Pd, or a mixture thereof. In analternative preferred embodiment, the metal hydrogenation component canbe a combination of a non-noble Group 8-10 metal with a Group 6 metal.Suitable combinations can include Ni, Co, or Fe with Mo or W, preferablyNi with Mo or W.

The metal hydrogenation component may be added to the dewaxing catalystin any convenient manner. One technique for adding the metalhydrogenation component is by incipient wetness. For example, aftercombining a zeolite and a binder, the combined zeolite and binder can beextruded into catalyst particles. These catalyst particles can then beexposed to a solution containing a suitable metal precursor.Alternatively, metal can be added to the catalyst by ion exchange, wherea metal precursor is added to a mixture of zeolite (or zeolite andbinder) prior to extrusion.

The amount of metal in the dewaxing catalyst can be at least 0.1 wt %based on catalyst, or at least 0.15 wt %, or at least 0.2 wt %, or atleast 0.25 wt %, or at least 0.3 wt %, or at least 0.5 wt % based oncatalyst. The amount of metal in the catalyst can be 20 wt % or lessbased on catalyst, or 10 wt % or less, or 5 wt % or less, or 2.5 wt % orless, or 1 wt % or less. For aspects where the metal is Pt, Pd, anotherGroup 8-10 noble metal, or a combination thereof, the amount of metalcan be from 0.1 to 5 wt %, preferably from 0.1 to 2 wt %, or 0.25 to 1.8wt %, or 0.4 to 1.5 wt %. For aspects where the metal is a combinationof a non-noble Group 8-10 metal with a Group 6 metal, the combinedamount of metal can be from 0.5 wt % to 20 wt %, or 1 wt % to 15 wt %,or 2.5 wt % to 10 wt %.

Preferably, a dewaxing catalyst can be a catalyst with a low ratio ofsilica, to alumina. For example, for ZSM-48, the ratio of silica toalumina in the zeolite can be less than 200:1, or less than 110:1, orless than 100:1, or less than 90:1, or less than 80:1. In particular,the ratio of silica to alumina can be from 30:1 to 200:1, or 60:1 to110:1, or 70:1 to 100:1.

A dewaxing catalyst can also include a binder. In some embodiments, thedewaxing catalysts used in process according to the invention areformulated using a low surface area binder, a low surface area binderrepresents a binder with a surface area of 100 m²/g or less, or 80 m²/gor less, or 70 m²/g or less, such as down to 40 m²/g or still lower.

Alternatively, the binder and the zeolite particle size can be selectedto provide a catalyst with a desired ratio of micropore surface area tototal surface area. In dewaxing catalysts used according to theinvention, the micropore surface area corresponds to surface area fromthe unidimensional pores of zeolites in the dewaxing catalyst. The totalsurface corresponds to the micropore surface area plus the externalsurface area. Any binder used in the catalyst will not contribute to themicropore surface area and will not significantly increase the totalsurface area of the catalyst. The external surface area represents thebalance of the surface area of the total catalyst minus the microporesurface area. Both the binder and zeolite can contribute to the value ofthe external surface area. Preferably, the ratio of micropore surfacearea to total surface area for a dewaxing catalyst will be equal to orgreater than 25%.

A zeolite (or other zeolitic material) can be combined with binder inany convenient manner. For example, a bound catalyst can be produced bystarting with powders of both the zeolite and binder, combining andmulling the powders with added water to form a mixture, and thenextruding the mixture to produce a bound catalyst of a desired size.Extrusion aids can also be used to modify the extrusion flow propertiesof the zeolite and binder mixture. The amount of framework alumina inthe catalyst may range from 0.1 to 3.33 wt %, or 0.1 to 2.7 wt %, or 0.2to 2 wt %, or 0.3 to 1 wt %.

In yet another embodiment, a binder composed of two or more metal oxidescan also be used. In such an embodiment, the weight percentage of thelow surface area binder is preferably greater than the weight percentageof the higher surface area binder.

Alternatively, if both metal oxides used for forming a mixed metal oxidebinder have a sufficiently low surface area, the proportions of eachmetal oxide in the binder are less important. When two or more metaloxides are used to form a binder, the two metal oxides can beincorporated into the catalyst by any convenient method. For example,one binder can be mixed with the zeolite during formation of the zeolitepowder, such as during spray drying. The spray dried zeolite/binderpowder can then be mixed with the second metal oxide binder prior toextrusion. In an aspect, the dewaxing catalyst can be self-bound anddoes not contain a binder. Process conditions in a catalytic dewaxingzone can include a temperature of from 200 to 450° C., preferably 270 to400° C., a hydrogen partial pressure of from 1.8 to 34.6 mPa (˜250 to˜5000 psi), preferably 4.8 to 20.8 mPa, a liquid hourly space velocityof from 0.2 to 10 hr⁻¹, preferably 0.5 to 3.0 hr⁻¹, and a hydrogencirculation rate of from 35.6 to 1781 m³/m³ (˜200 to ˜10,000 scf/B),preferably 178 to 890.6 m³/m³ (˜1000 to ˜5000 scf/B).

In various aspects, a hydrofinishing and/or aromatic saturation processcan also be provided. The hydrofinishing and/or aromatic saturation canoccur prior to dewaxing and/or after dewaxing. The hydrofinishing and/oraromatic saturation can occur either before or after fractionation. Ifhydrofinishing and/or aromatic saturation occurs after fractionation,the hydrofinishing can be performed on one or more portions of thefractionated product, such as being performed on one or more lubricantbase stock portions. Alternatively, the entire effluent from the lasthydrocracking or dewaxing process can be hydrofinished and/or undergoaromatic saturation.

In some situations, a hydrofinishing process and an aromatic saturationprocess can refer to a single process performed using the same catalyst.Alternatively, one type of catalyst or catalyst system can be providedto perform aromatic saturation, while a second catalyst or catalystsystem can be used for hydrofinishing. Typically a hydrofinishing and/oraromatic saturation process will be performed in a separate reactor fromdewaxing or hydrocracking processes for practical reasons, such asfacilitating use of a lower temperature for the hydrofinishing oraromatic saturation process. However, an additional hydrofinishingreactor following a hydrocracking or dewaxing process but prior tofractionation could still be considered part of a second stage of areaction system conceptually.

Hydrofinishing and/or aromatic saturation catalysts can includecatalysts containing Group 6 metals, Group 8-10 metals, and mixturesthereof. In an embodiment, preferred metals include at least one metalsulfide having a strong hydrogenation function. In another embodiment,the hydrofinishing catalyst can include a Group 8-10 noble metal, suchas Pt, Pd, or a combination thereof. The mixture of metals may also bepresent as bulk metal catalysts wherein the amount of metal is 30 wt. %or greater based on catalyst. Suitable metal oxide supports include lowacidic oxides such as silica, alumina, silica-aluminas or titania,preferably alumina. The preferred hydrofinishing catalysts for aromaticsaturation will comprise at least one metal having relatively stronghydrogenation function on a porous support. Typical support materialsinclude amorphous or crystalline oxide materials such as alumina,silica, and silica-alumina. The support materials may also be modified,such as by halogenation, or in particular fluorination. The metalcontent of the catalyst is often as high as 20 weight percent fornon-noble metals. In an embodiment, a preferred hydrofinishing catalystcan include a crystalline material belonging to the M41S class or familyof catalysts. The M41S family of catalysts are mesoporous materialshaving high silica content. Examples include MCM-41, MCM-48 and MCM-50.A preferred member of this class is MCM-41. If separate catalysts areused for aromatic saturation and hydrofinishing, an aromatic saturationcatalyst can be selected based on activity and/or selectivity foraromatic saturation, while a hydrofinishing catalyst can be selectedbased on activity for improving product specifications, such as productcolor and polynuclear aromatic reduction.

Hydrofinishing conditions can include temperatures from 125° C. to 425°C., preferably 180° C. to 280° C., total pressures from 500 psig (˜3.4MPag) to 3000 psig (˜20.7 MPag), preferably 1500 psig (˜10.3 MPag) to2500 psig (˜17.2 MPag), and liquid hourly space velocity (LHSV) from 0.1hr⁻¹ to 5 hr⁻¹, preferably 0.5 hr⁻¹ to 1.5 hr⁻¹.

A second fractionation or separation can be performed at one or morelocations after a second or subsequent stage. In some aspects, afractionation can be performed after hydrocracking in the second stagein the presence of the USY catalyst under sweet conditions. At least alubricant boiling range portion of the second stage hydrocrackingeffluent can then be sent to a dewaxing and/or hydrofinishing reactorfor further processing. In some aspects, hydrocracking and dewaxing canbe performed prior to a second fractionation. In some aspects,hydrocracking, dewaxing, and aromatic saturation can be performed priorto a second fractionation. Optionally, aromatic saturation and/orhydrofinishing can be performed before a second fractionation, after asecond fractionation, or both before and after.

Example 1—Block Processing of Light Neutral and Heavy Neutral

The following is a prophetic example. A processing configuration similarto the configurations shown in FIGS. 1 to 3 is used to process afeedstock to form a light neutral base stock product and a heavy neutralbase stock product. The full range feed is processed in the first (sour)processing stage. Fractionation is then used to form separatehydroprocessed feeds for light neutral base stock production and heavyneutral base stock production. After fractionation, the feed for lightneutral base stock production has a viscosity index of 85 and the feedfor heavy neutral base stock production has a viscosity index of 90.Blocked operation is then used to process the feeds. The conversion inthe second stage hydrocracking reactor for the light neutral feed issufficient to produce a light neutral base stock product with aviscosity index of 135 and a viscosity of roughly 4.0 cSt. The amount ofconversion for the light neutral feed in the second stage hydrocrackingreactor is roughly 60 wt % relative to 370° C. The conversion in thesecond stage hydrocracking reactor for the heavy neutral feed issufficient to produce a heavy neutral base stock product with aviscosity index of 95 and a viscosity of roughly 11 cSt. The amount ofconversion for the heavy neutral feed in the second stage hydrocrackingreactor is roughly 10 wt % relative to 370° C.

Example 2—Reactor Temperature Management During Heavy Neutral Processing

The following is a prophetic example. A processing configuration similarto FIG. 2 can be used to perform second stage processing for productionof a heavy neutral feedstock, such as production of a heavy neutralfeedstock as part of block operation of the processing configuration forproduction of a plurality of lubricant base stocks. In this example, atleast one initial catalyst bed in the first reactor stage (shown as 110in FIG. 2) corresponds to a bed of aromatic saturation catalyst.Additionally, at least one subsequent catalyst bed in the first reactorstage corresponds to a bed of hydrocracking catalyst, such as ahydrocracking catalyst including Pt supported on a USY zeolite. Thus,the first reactor stage corresponds to a hydrocracking stage. In thisexample, at least one initial catalyst bed in the second reactor (shownas 120 in FIG. 2) corresponds to a bed of dewaxing catalyst. Thus, thesecond reactor stage corresponds to a dewaxing stage. Optionally, atleast one subsequent catalyst bed in the second reactor can correspondto an aromatic saturation catalyst. It is noted that references to acatalyst bed in this example are understood to include configurationswhere a bed is only partially filled with a type of catalyst and/orwhere a single reactor bed for holding catalyst contains multiple layers(or stacked beds) of different catalyst types. The third reactor (shownas 140 in FIG. 2) can include one or more beds of aromatic saturationcatalyst.

In this example, at the beginning of processing of the heavy neutralfeed, the temperature required by the first (hydrocracking) reactor maybe low. The initial low temperature can be due in part to needing only alimited amount of viscosity index uplift to meet a desired target forheavy neutral production and/or due in part to a relatively highactivity for the catalyst(s) in the reactor. As an example, a start ofrun temperature for the inlet to the first reactor can be 560° F. (293°C.). Based on the reactions in the reactor, the start of run temperaturefor the exit of the first reactor can be 585° F. (307° C.). Thistemperature can be below the desired temperature for performing dewaxingin order to achieve a desired target for cold flow properties for thefinal heavy neutral product. For example, the start of run temperaturefor the inlet to the second reactor can be 600° F. (316° C.).

After a period of time, processing of the heavy neutral feed can resultin deactivation of the catalysts in the various reactors. This aging canbe due to coke formation and/or any other typical reason that ahydroprocessing catalyst has a reduction in activity due to exposure toa feed under hydroprocessing conditions. To compensate for catalystaging, the temperature of the first reactor can be increased so that thedesired amount of viscosity index uplift is still achieved, while thetemperature of the second reactor can be increased so that the desiredamount of improvement in cold flow properties is achieved. Becausedewaxing catalysts often age more slowly than hydrocracking catalysts,the amount of temperature increase required for the first reactor may begreater than the amount for the second reactor. As a result, by the endof the processing run, the inlet temperature for the first reactor canbe 575° C. At this higher temperature, more reaction can occur, leadingto a greater disparity between the temperatures for the first reactorinlet and the first reactor outlet. The end of run temperature for thefirst reactor outlet can be 640° F. (338° C.). Optionally, a portion ofthis greater disparity can also correspond to removing quench streamsbetween the initial aromatic saturation catalyst bed(s) and thesubsequent hydrocracking catalyst bed(s). By contrast, the amount ofcatalyst aging for the dewaxing catalyst can result in a more modesttemperature increase, so that the reactor inlet temperature for thesecond reactor at the end of the run can be 630° F. (332° C.).

Based on a comparison of the difference between the first reactor outlettemperatures and the second reactor inlet temperatures, the temperatureprofile between the first and second reactors is flipped between thestart of the processing run and the end of the processing run. At thestart of the processing run, the first reactor outlet temperature iscolder than the second reactor inlet temperature by 9° C. At the end ofthe processing run, the first reactor outlet temperature is warmer thanthe second reactor inlet temperature by 6° C. The heated hydrogen lines281 and/or 282 can be used to facilitate achieving these desiredtemperature differentials. For example, at the start of the processingrun, additional heated hydrogen can be delivered to the second reactorto provide the additional temperature needed to achieve the desiredstart of run temperature for dewaxing. Additionally or alternately, heatexchangers could be used to provide this temperature increase. Overtime, the amount of heated hydrogen delivered via heated hydrogen line282 can be reduced, until at some point during the processing run theinlet temperature for the dewaxing reactor falls below the exittemperature for the hydrocracking reactor. As the processing runcontinues, heated hydrogen line 281 can optionally be used to provideadditional heat for the first (hydrocracking) reactor. Additionally oralternately, additional heating of the feed can be used to achieve thetemperature increases for the first reactor that are needed to offsetcatalyst aging.

A similar switch in the order reactor temperatures could also occur, forexample, during second stage processing of a feed for brightstockproduction. In this additional example, the same type of catalystsystems described above can be used. The start of run temperatures forthe hydrocracking reactor inlet/hydrocracking reactor outlet can be 560°F. (293° C.)/585° F. (307° C.), which are similar to the correspondingtemperatures for the heavy neutral processing example. Due in part to ahigher amount of desired viscosity index uplift for the final product,the end of run temperatures for the hydrocracking reactor inlet/outletcan be 610° F. (321° C.)/700° F. (371° C.). For dewaxing, the start ofrun inlet temperature can be 650° F. (343° C.), while the end of runinlet temperature can be 690° F. (366° C.). Thus, for this example, theoutlet of the hydrocracking reactor at start of run is colder than thedewaxing inlet by more than 30° C., while the outlet of thehydrocracking reactor is warmer than the dewaxing inlet at end of run by5° C.

ADDITIONAL EMBODIMENTS Embodiment 1

A method for producing lubricant boiling range product using blockedoperation, comprising: fractionating a hydroprocessed feedstock to format least a first lubricant boiling range fraction comprising a 343° C.+portion and a second lubricant boiling range fraction having a T10distillation point of at least 343° C. and a kinematic viscosity at 100°C. of 6.0 cSt or more, the 343° C.+ portion of the first lubricantboiling range fraction having a kinematic viscosity at 100° C. of 1.5cSt to 6.0 cSt, the second lubricant boiling range fraction optionallyhaving a viscosity index that is greater than the viscosity index of thefirst lubricant boiling range fraction; hydrocracking at least a portionof the first lubricant boiling range fraction in the presence ofhydrocracking catalyst under first hydrocracking conditions comprising afirst hydrocracking inlet temperature and a first hydrocracking outlettemperature in a first reactor to form a first hydrocracked effluent,the first hydrocracking conditions comprising 10 wt % to 80 wt %conversion relative to 370° C. of the at least a portion of the firstlubricant boiling range fraction; dewaxing at least a portion of thefirst hydrocracked effluent under first catalytic dewaxing conditions ina second reactor to form a first dewaxed effluent; hydrocracking atleast a portion of the second lubricant boiling range fraction in thepresence of the hydrocracking catalyst under second hydrocrackingconditions in the first reactor to form a second hydrocracked effluent,the second hydrocracking conditions comprising 1 wt % to 25 wt %conversion relative to 370° C. of the at least a portion of the secondlubricant boiling range fraction, the second hydrocracking conditionscomprising a second hydrocracking inlet temperature and a secondhydrocracking outlet temperature, the conversion relative to 370° C. forthe first hydrocracking conditions being at least 10 wt % greater (or atleast 20 wt % greater, or at least 30 wt % greater) than the conversionrelative to 370° C. for the second hydrocracking conditions; dewaxing atleast a portion of the second hydrocracked effluent under secondcatalytic dewaxing conditions in the second reactor to form a seconddewaxed effluent; fractionating at least a portion of the first dewaxedeffluent to form at least a first fuels boiling range product and afirst lubricant boiling range product; and fractionating at least aportion of the second dewaxed effluent to form at least a second fuelsboiling range product and a second lubricant boiling range product, aviscosity index of the second lubricant boiling range product beinglower than a viscosity index of the first lubricant boiling rangeproduct by at least 5 (or at least 15, or at least 25).

Embodiment 2

The method of Embodiment 1, further comprising hydroprocessing afeedstock under hydroprocessing conditions to form the hydroprocessedfeedstock.

Embodiment 3

A method for producing lubricant boiling range product using blockedoperation, comprising: fractionating a feedstock to form at least afirst lubricant boiling range fraction comprising a 343° C.+ portion anda second lubricant boiling range fraction having a T10 distillationpoint of at least 343° C. and a kinematic viscosity at 100° C. of 6.0cSt or more, the 343° C.+ portion having a kinematic viscosity at 100°C. of 1.5 cSt to 6.0 cSt, the second lubricant boiling range fractionoptionally having a viscosity index that is greater than the viscosityindex of the first lubricant boiling range fraction; hydroprocessing atleast a portion of the first lubricant boiling range fraction underfirst hydroprocessing conditions to form a first hydroprocessedeffluent; hydrocracking at least a portion of the first hydroprocessedeffluent in the presence of hydrocracking catalyst under firsthydrocracking conditions in a first reactor to form a first hydrocrackedeffluent, the first hydroprocessing conditions and the firsthydrocracking conditions comprising a combined conversion of the firstlubricant boiling range fraction of 40 wt % to 80 wt % relative to 370°C.; dewaxing at least a portion of the first hydrocracked effluent underfirst catalytic dewaxing conditions in a second reactor to form a firstdewaxed effluent; hydroprocessing at least a portion of the secondlubricant boiling range fraction under second hydroprocessing conditionsto form a second hydroprocessed effluent; hydrocracking at least aportion of the second hydroprocessed effluent in the presence of thehydrocracking catalyst under second hydrocracking conditions in thefirst reactor to form a second hydrocracked effluent, the secondhydroprocessing conditions and the second hydrocracking conditionscomprising a combined conversion of the second lubricant boiling rangefraction of 20 wt % to 60 wt % relative to 370° C.; dewaxing at least aportion of the second hydrocracked effluent under second catalyticdewaxing conditions in the second reactor to form a second dewaxedeffluent; fractionating at least a portion of the first dewaxed effluentto form at least a first fuels boiling range product and a firstlubricant boiling range product; and fractionating at least a portion ofthe second dewaxed effluent to form at least a second fuels boilingrange product and a second lubricant boiling range product, a viscosityindex of the second lubricant boiling range product being lower than aviscosity index of the first lubricant boiling range product by at least5 (or at least 15, or at least 25).

Embodiment 4

The method of any of the above embodiments, wherein the second catalyticdewaxing conditions comprise a second dewaxing inlet temperature that isgreater than the second hydrocracking outlet temperature (or at least 5°C. greater, or at least 10° C. greater, or at least 20° C., or at least30° C.), or wherein the first catalytic dewaxing conditions comprise afirst dewaxing inlet temperature that is less than the firsthydrocracking outlet temperature (or at least 5° C. less, or at least10° C. less, or at least 20° C. less), or a combination thereof.

Embodiment 5

The method of any of the above embodiments, wherein the second catalyticdewaxing conditions comprise introducing a heated hydrogen-containingstream into the second reactor.

Embodiment 6

The method of any of the above embodiments, wherein one or more of thehydroprocessed feedstock, the first lubricant boiling range fraction,and the second boiling range fraction comprise 100 wppm or less ofsulfur; or wherein the hydrocracking catalyst comprises 0.1 wt % to 5.0wt % of a noble metal supported on the hydrocracking catalyst; orwherein the hydrocracking catalyst comprises USY zeolite having a unitcell size of 24.30 Å or less, a silica to alumina ratio of at least 50,and an Alpha value of 20 or less; or a combination thereof.

Embodiment 7

The method of any of the above embodiments, wherein fractionating thehydroprocessed feedstock further comprising forming a fuels boilingrange fraction.

Embodiment 8

The method of any of the above embodiments, i) further comprisingstoring the at least a portion of the first lubricant boiling rangefraction prior to the hydrocracking of the at least a portion of thefirst lubricant boiling range fraction, ii) further comprising storingthe at least a portion of the second lubricant boiling range fractionprior to the hydrocracking of the at least a portion of the secondlubricant boiling range fraction, or iii) a combination of i) and ii).

Embodiment 9

The method of any of the above embodiments, wherein the first reactorfurther comprises an aromatic saturation catalyst, wherein the secondreactor further comprises an aromatic saturation catalyst, or acombination thereof.

Embodiment 10

The method of any of the above embodiments, wherein the first lubricantboiling range product comprises a viscosity index of at least 125 (or atleast 130, or at least 135); or wherein the second lubricant boilingrange product comprises a viscosity index of at least 80 (or at least85, or at least 90); or wherein the viscosity index of the secondlubricant boiling range product is lower than the viscosity index of thefirst lubricant boiling range product by at least 15 (or at least 25);or a combination thereof.

Embodiment 11

The method of any of the above embodiments, wherein the first dewaxingconditions are substantially similar to the second dewaxing conditions;or wherein the first hydrocracking inlet temperature is greater than thesecond hydrocracking inlet temperature by at least 10° C. (or at least15° C., or at least 20° C.); or a combination thereof.

Embodiment 12

The method of any of the above embodiments, further comprising: exposingat least a portion of the first dewaxed effluent to an aromaticsaturation catalyst in a third reactor under first aromatic saturationconditions to form a first saturated product comprising the firstlubricant boiling range product, the first lubricant boiling rangeproduct having an aromatics content of 2.0 wt % or less; and exposing atleast a portion of the second dewaxed effluent to the aromaticsaturation catalyst in the third reactor under second aromaticsaturation conditions to form a second saturated product comprising thesecond lubricant boiling range product, the second lubricant boilingrange product having an aromatics content of 2.0 wt % or less, the firstaromatic saturation conditions optionally being substantially similar tothe second aromatic saturation conditions, the second reactor optionallyfurther comprising a second aromatic saturation catalyst, the at least aportion of the first hydrocracked effluent contacting at least a portionof the second aromatic saturation catalyst prior to being exposed to thedewaxing catalyst.

Embodiment 13

A multi-reactor reaction system, comprising: a first reactor comprisinga first gas inlet, hydrocracking reactor inlet, a hydrocracking reactoroutlet, and a hydrocracking catalyst comprising 0.1 wt % to 5.0 wt % ofa Group 8-10 noble metal supported on the hydrocracking catalyst; asecond reactor comprising a second gas inlet, a dewaxing reactor inlet,a dewaxing reactor outlet, and a dewaxing catalyst, the dewaxing reactorinlet being in fluid communication with the hydrocracking reactoroutlet; a third reactor comprising an aromatic saturation inlet, anaromatic saturation outlet, and a first aromatic saturation catalyst,the aromatic saturation inlet being in fluid communication with thedewaxing reactor outlet; and a heater comprising a feed heater flow pathand a hydrogen heater flow path, the feed heater flow path being influid communication with the hydrocracking reactor inlet, the hydrogenheater flow path being in fluid communication with the first gas inletand the second gas inlet, wherein optionally at least a portion of asecond aromatic saturation catalyst is located upstream from thedewaxing catalyst relative to a direction of flow in the second reactor.

Embodiment 14

The system of Embodiment 13, wherein the third reactor further comprisesa third gas inlet in fluid communication with the hydrogen heater flowpath, or wherein the hydrocracking reactor inlet comprises the first gasinlet, or wherein the second gas inlet is in selective fluidcommunication with the heated hydrogen flow path, or a combinationthereof.

Embodiment 15

The system of Embodiment 13 or 14, the system further comprising a firststorage tank and a second storage tank, the first storage tank and thesecond storage tank being in selective fluid communication with the feedheater flow path, the first storage tank comprising a first lubricantboiling range feed comprising a 343° C.+ portion, the 343° C.+ portionof the first lubricant boiling range feed having a kinematic viscosityat 100° C. of 1.5 cSt to 6.0 cSt, the second storage tank comprising asecond lubricant boiling range feed having a T10 distillation point ofat least 343° C. and a kinematic viscosity at 100° C. of 6.0 cSt ormore, the second lubricant boiling range feed optionally having aviscosity index that is greater than the viscosity index of the firstlubricant boiling range feed.

Embodiment 16

A method for producing a lubricant boiling range product, comprising:hydrocracking a lubricant boiling range fraction in the presence ofhydrocracking catalyst under first hydrocracking conditions comprising afirst hydrocracking inlet temperature and a first hydrocracking outlettemperature in a first reactor to form a first hydrocracked effluent,the first hydrocracking conditions comprising a first amount ofconversion relative to 370° C. of the at least a portion of thelubricant boiling range fraction; dewaxing at least a portion of thefirst hydrocracked effluent under first catalytic dewaxing conditionscomprising a first dewaxing inlet temperature in a second reactor toform a first dewaxed effluent, the first dewaxing inlet temperaturebeing greater than the first hydrocracking outlet temperature by atleast 3° C. (or at least 5° C., or at least 8° C., or at least 10° C.);modifying the conditions for hydrocracking while performinghydrocracking of the lubricant boiling range fraction; hydrocracking thelubricant boiling range fraction in the presence of the hydrocrackingcatalyst under modified hydrocracking conditions comprising a modifiedhydrocracking inlet temperature and a modified hydrocracking outlettemperature in the first reactor to form a second hydrocracked effluent,the modified hydrocracking conditions comprising a second amount ofconversion relative to 370° C. of the at least a portion of thelubricant boiling range fraction, the second amount of conversionrelative to 370° C. being different from the first amount of conversionrelative to 370° C. by 5 wt % or less; dewaxing at least a portion ofthe second hydrocracked effluent under second catalytic dewaxingconditions comprising a second dewaxing inlet temperature in the secondreactor to form a second dewaxed effluent, the second dewaxing inlettemperature being less than the modified hydrocracking outlettemperature by at least 3° C. (or at least 5° C., or at least 8° C., orat least 10° C.); fractionating at least a portion of the first dewaxedeffluent to form at least a first fuels boiling range product and afirst lubricant boiling range product; and fractionating at least aportion of the second dewaxed effluent to form at least a second fuelsboiling range product and a second lubricant boiling range product, aviscosity index of the second lubricant boiling range product beingdifferent than a viscosity index of the first lubricant boiling rangeproduct by 5 or less (or 3 or less, or 1 or less).

Embodiment 17

The method of Embodiment 16, wherein the lubricant boiling rangefraction has a T10 distillation point of at least 343° C. and akinematic viscosity at 100° C. of 6.0 cSt or more; or wherein thelubricant boiling range fraction has a T10 distillation point of atleast 371° C. and a kinematic viscosity at 100° C. of 15 cSt or more; orwherein the lubricant boiling range fraction comprises a 343° C.+portion, the 343° C.+ portion having a kinematic viscosity at 100° C. of1.5 cSt to 6.0 cSt.

Embodiment 18

The method of Embodiment 16 or 17, wherein the first catalytic dewaxingconditions comprise introducing a heated hydrogen-containing stream intothe second reactor.

Embodiment 19

The method of any of Embodiments 16 to 18, further comprisinghydrofinishing the at least a portion of the first dewaxed effluentprior to fractionation, after fractionation, or a combination thereof,the hydrofinishing comprising exposing at least a portion of the firstdewaxed effluent to an aromatic saturation catalyst in a third reactorunder first aromatic saturation conditions to form a first saturatedproduct comprising the first lubricant boiling range product, the firstlubricant boiling range product having an aromatics content of 2.0 wt %or less.

Embodiment 20

The method of any of Embodiments 16 to 19, further comprising modifyingthe conditions for dewaxing while performing dewaxing of hydrocrackedeffluent produced during the modification of the conditions forhydrocracking, the second dewaxing conditions comprise modified dewaxingconditions, the second dewaxing inlet temperature comprising a modifieddewaxing inlet temperature.

Embodiment 21

The method of any of Embodiments 16 to 20, further comprising modifyingthe conditions for dewaxing i) while performing dewaxing of the at leasta portion of the first hydrocracked effluent, ii) while performingdewaxing of the at least a portion of the second hydrocracked effluent,or iii) a combination of i) and ii).

Embodiment 22

The method of any of Embodiments 16 to 21, wherein at least one of thehydroprocessed feedstock and the lubricant boiling range fractioncomprise 100 wppm or less of sulfur; or wherein the hydrocrackingcatalyst comprises 0.1 wt % to 5.0 wt % of a noble metal supported onthe hydrocracking catalyst; or wherein the hydrocracking catalystcomprises USY zeolite having a unit cell size of 24.30 Å or less, asilica to alumina ratio of at least 50, and an Alpha value of 20 orless; or a combination thereof.

When numerical lower limits and numerical upper limits are listedherein, ranges from any lower limit to any upper limit are contemplated.While the illustrative embodiments of the invention have been describedwith particularity, it will be understood that various othermodifications will be apparent to and can be readily made by thoseskilled in the art without departing from the spirit and scope of theinvention. Accordingly, it is not intended that the scope of the claimsappended hereto be limited to the examples and descriptions set forthherein but rather that the claims be construed as encompassing all thefeatures of patentable novelty which reside in the present invention,including all features which would be treated as equivalents thereof bythose skilled in the art to which the invention pertains.

The present invention has been described above with reference tonumerous embodiments and specific examples. Many variations will suggestthemselves to those skilled in this art in light of the above detaileddescription. All such obvious variations are within the full intendedscope of the appended claims.

1. A method for producing lubricant boiling range product using blockedoperation, comprising: fractionating a hydroprocessed feedstock to format least a first lubricant boiling range fraction comprising a 343° C.+portion and a second lubricant boiling range fraction having a T10distillation point of at least 343° C. and a kinematic viscosity at 100°C. of 6.0 cSt or more, the 343° C.+ portion of the first lubricantboiling range fraction having a kinematic viscosity at 100° C. of 1.5cSt to 6.0 cSt; hydrocracking at least a portion of the first lubricantboiling range fraction in the presence of hydrocracking catalyst underfirst hydrocracking conditions comprising a first hydrocracking inlettemperature and a first hydrocracking outlet temperature in a firstreactor to form a first hydrocracked effluent, the first hydrocrackingconditions comprising 10 wt % to 80 wt % conversion relative to 370° C.of the at least a portion of the first lubricant boiling range fraction;dewaxing at least a portion of the first hydrocracked effluent underfirst catalytic dewaxing conditions in a second reactor to form a firstdewaxed effluent; hydrocracking at least a portion of the secondlubricant boiling range fraction in the presence of the hydrocrackingcatalyst under second hydrocracking conditions in the first reactor toform a second hydrocracked effluent, the second hydrocracking conditionscomprising 1 wt % to 25 wt % conversion relative to 370° C. of the atleast a portion of the second lubricant boiling range fraction, thesecond hydrocracking conditions comprising a second hydrocracking inlettemperature and a second hydrocracking outlet temperature, theconversion relative to 370° C. for the first hydrocracking conditionsbeing at least 10 wt % greater than the conversion relative to 370° C.for the second hydrocracking conditions; dewaxing at least a portion ofthe second hydrocracked effluent under second catalytic dewaxingconditions in the second reactor to form a second dewaxed effluent;fractionating at least a portion of the first dewaxed effluent to format least a first fuels boiling range product and a first lubricantboiling range product; and fractionating at least a portion of thesecond dewaxed effluent to form at least a second fuels boiling rangeproduct and a second lubricant boiling range product, a viscosity indexof the second lubricant boiling range product being lower than aviscosity index of the first lubricant boiling range product by at least5.
 2. The method of claim 1, wherein the second catalytic dewaxingconditions comprise a second dewaxing inlet temperature that is greaterthan the second hydrocracking outlet temperature, or wherein the firstcatalytic dewaxing conditions comprise a first dewaxing inlettemperature that is less than the first hydrocracking outlettemperature; or a combination thereof.
 3. The method of claim 1, whereinthe second lubricant boiling range fraction comprises a viscosity indexthat is greater than the viscosity index of the first lubricant boilingrange fraction
 4. The method of claim 1, wherein the second catalyticdewaxing conditions comprise introducing a heated hydrogen-containingstream into the second reactor.
 5. The method of claim 1, furthercomprising hydroprocessing a feedstock under hydroprocessing conditionsto form the hydroprocessed feedstock.
 6. The method of claim 1, whereinone or more of the hydroprocessed feedstock, the first lubricant boilingrange fraction, and the second boiling range fraction comprise 100 wppmor less of sulfur; or wherein the hydrocracking catalyst comprises 0.1wt % to 5.0 wt % of a noble metal supported on the hydrocrackingcatalyst; or a combination thereof.
 7. The method of claim 1, whereinfractionating the hydroprocessed feedstock further comprising forming afuels boiling range fraction.
 8. The method of claim 1, i) furthercomprising storing the at least a portion of the first lubricant boilingrange fraction prior to the hydrocracking of the at least a portion ofthe first lubricant boiling range fraction, ii) further comprisingstoring the at least a portion of the second lubricant boiling rangefraction prior to the hydrocracking of the at least a portion of thesecond lubricant boiling range fraction, or iii) a combination of i) andii).
 9. The method of claim 1, wherein the first reactor furthercomprises an aromatic saturation catalyst, wherein the second reactorfurther comprises an aromatic saturation catalyst, or a combinationthereof.
 10. The method of claim 1, wherein the hydrocracking catalystcomprising USY zeolite having a unit cell size of 24.30 Å or less, asilica to alumina ratio of at least 50, and an Alpha value of 20 orless, the hydrocracking catalyst further comprising 0.1 wt % to 5.0 wt %of a Group 8-10 noble metal supported on the hydrocracking catalyst. 11.The method of claim 1, wherein the first lubricant boiling range productcomprises a viscosity index of at least
 125. 12. The method of claim 1,wherein the second lubricant boiling range product comprises a viscosityindex of at least
 80. 13. The method of claim 1, wherein the viscosityindex of the second lubricant boiling range product is lower than theviscosity index of the first lubricant boiling range product by at least15.
 14. The method of claim 1, wherein the first dewaxing conditions aresubstantially similar to the second dewaxing conditions.
 15. The methodof claim 1, wherein the first hydrocracking inlet temperature is greaterthan the second hydrocracking inlet temperature by at least 10° C. 16.The method of claim 1, further comprising: exposing at least a portionof the first dewaxed effluent to an aromatic saturation catalyst in athird reactor under first aromatic saturation conditions to form a firstsaturated product comprising the first lubricant boiling range product,the first lubricant boiling range product having an aromatics content of2.0 wt % or less; and exposing at least a portion of the second dewaxedeffluent to the aromatic saturation catalyst in the third reactor undersecond aromatic saturation conditions to form a second saturated productcomprising the second lubricant boiling range product, the secondlubricant boiling range product having an aromatics content of 2.0 wt %or less.
 17. The method of claim 16, wherein the first aromaticsaturation conditions are substantially similar to the second aromaticsaturation conditions
 18. The method of claim 16, wherein the secondreactor further comprises a second aromatic saturation catalyst, the atleast a portion of the first hydrocracked effluent contacting at least aportion of the second aromatic saturation catalyst prior to beingexposed to the dewaxing catalyst.
 19. A method for producing lubricantboiling range product using blocked operation, comprising: fractionatinga feedstock to form at least a first lubricant boiling range fractioncomprising a 343° C.+ portion and a second lubricant boiling rangefraction having a T10 distillation point of at least 343° C. and akinematic viscosity at 100° C. of 6.0 cSt or more, the 343° C.+ portionhaving a kinematic viscosity at 100° C. of 1.5 cSt to 6.0 cSt;hydroprocessing at least a portion of the first lubricant boiling rangefraction under first hydroprocessing conditions to form a firsthydroprocessed effluent; hydrocracking at least a portion of the firsthydroprocessed effluent in the presence of hydrocracking catalyst underfirst hydrocracking conditions comprising a in a first reactor to form afirst hydrocracked effluent, the first hydroprocessing conditions andthe first hydrocracking conditions comprising a combined conversion ofthe first lubricant boiling range fraction of 40 wt % to 80 wt %relative to 370° C.; dewaxing at least a portion of the firsthydrocracked effluent under first catalytic dewaxing conditions in asecond reactor to form a first dewaxed effluent; hydroprocessing atleast a portion of the second lubricant boiling range fraction undersecond hydroprocessing conditions to form a second hydroprocessedeffluent; hydrocracking at least a portion of the second hydroprocessedeffluent in the presence of the hydrocracking catalyst under secondhydrocracking conditions in the first reactor to form a secondhydrocracked effluent, the second hydroprocessing conditions and thesecond hydrocracking conditions comprising a combined conversion of thesecond lubricant boiling range fraction of 20 wt % to 60 wt % relativeto 370° C.; dewaxing at least a portion of the second hydrocrackedeffluent under second catalytic dewaxing conditions in the secondreactor to form a second dewaxed effluent; fractionating at least aportion of the first dewaxed effluent to form at least a first fuelsboiling range product and a first lubricant boiling range product; andfractionating at least a portion of the second dewaxed effluent to format least a second fuels boiling range product and a second lubricantboiling range product, a viscosity index of the second lubricant boilingrange product being lower than a viscosity index of the first lubricantboiling range product by at least
 5. 20. A multi-reactor reactionsystem, comprising: a first reactor comprising a first gas inlet,hydrocracking reactor inlet, a hydrocracking reactor outlet, and ahydrocracking catalyst comprising 0.1 wt % to 5.0 wt % of a Group 8-10noble metal supported on the hydrocracking catalyst; a second reactorcomprising a second gas inlet, a dewaxing reactor inlet, a dewaxingreactor outlet, and a dewaxing catalyst, the dewaxing reactor inletbeing in fluid communication with the hydrocracking reactor outlet; athird reactor comprising an aromatic saturation inlet, an aromaticsaturation outlet, and a first aromatic saturation catalyst, thearomatic saturation inlet being in fluid communication with the dewaxingreactor outlet; a heater comprising a feed heater flow path and ahydrogen heater flow path, the feed heater flow path being in fluidcommunication with the hydrocracking reactor inlet, the hydrogen heaterflow path being in fluid communication with the first gas inlet and thesecond gas inlet.
 21. The system of claim 20, wherein the third reactorfurther comprises a third gas inlet in fluid communication with thehydrogen heater flow path.
 22. The system of claim 20, wherein at leasta portion of a second aromatic saturation catalyst is located upstreamfrom the dewaxing catalyst relative to a direction of flow in the secondreactor.
 23. The system of claim 20, wherein the hydrocracking reactorinlet comprises the first gas inlet.
 24. The system of claim 20, thesystem further comprising a first storage tank and a second storagetank, the first storage tank and the second storage tank being inselective fluid communication with the feed heater flow path, the firststorage tank comprising a first lubricant boiling range feed comprisinga 343° C.+ portion, the 343° C.+ portion of the first lubricant boilingrange feed having a kinematic viscosity at 100° C. of 1.5 cSt to 6.0cSt, the second storage tank comprising a second lubricant boiling rangefeed having a T10 distillation point of at least 343° C. and a kinematicviscosity at 100° C. of 6.0 cSt or more.
 25. The system of claim 20,wherein the second gas inlet is in selective fluid communication withthe heated hydrogen flow path.
 26. A method for producing a lubricantboiling range product, comprising: hydrocracking a lubricant boilingrange fraction in the presence of hydrocracking catalyst under firsthydrocracking conditions comprising a first hydrocracking inlettemperature and a first hydrocracking outlet temperature in a firstreactor to form a first hydrocracked effluent, the first hydrocrackingconditions comprising a first amount of conversion relative to 370° C.of the at least a portion of the lubricant boiling range fraction;dewaxing at least a portion of the first hydrocracked effluent underfirst catalytic dewaxing conditions comprising a first dewaxing inlettemperature in a second reactor to form a first dewaxed effluent, thefirst dewaxing inlet temperature being greater than the firsthydrocracking outlet temperature by at least 3° C.; modifying theconditions for hydrocracking while performing hydrocracking of thelubricant boiling range fraction; hydrocracking the lubricant boilingrange fraction in the presence of the hydrocracking catalyst undermodified hydrocracking conditions comprising a modified hydrocrackinginlet temperature and a modified hydrocracking outlet temperature in thefirst reactor to form a second hydrocracked effluent, the modifiedhydrocracking conditions comprising a second amount of conversionrelative to 370° C. of the at least a portion of the lubricant boilingrange fraction, the second amount of conversion relative to 370° C.being different from the first amount of conversion relative to 370° C.by 5 wt % or less; dewaxing at least a portion of the secondhydrocracked effluent under second catalytic dewaxing conditionscomprising a second dewaxing inlet temperature in the second reactor toform a second dewaxed effluent, the second dewaxing inlet temperaturebeing less than the modified hydrocracking outlet temperature by atleast 3° C.; fractionating at least a portion of the first dewaxedeffluent to form at least a first fuels boiling range product and afirst lubricant boiling range product; and fractionating at least aportion of the second dewaxed effluent to form at least a second fuelsboiling range product and a second lubricant boiling range product, aviscosity index of the second lubricant boiling range product beingdifferent than a viscosity index of the first lubricant boiling rangeproduct by 5 or less.
 27. The method of claim 26, wherein the lubricantboiling range fraction has a T10 distillation point of at least 343° C.and a kinematic viscosity at 100° C. of 6.0 cSt or more.
 28. The methodof claim 26, wherein the lubricant boiling range fraction has a T10distillation point of at least 371° C. and a kinematic viscosity at 100°C. of 15 cSt or more.
 29. The method of claim 26, wherein the lubricantboiling range fraction comprises a 343° C.+ portion, the 343° C.+portion having a kinematic viscosity at 100° C. of 1.5 cSt to 6.0 cSt.30. The method of claim 26, wherein the first catalytic dewaxingconditions comprise introducing a heated hydrogen-containing stream intothe second reactor.
 31. The method of claim 26, further comprisinghydrofinishing the at least a portion of the first dewaxed effluentprior to fractionation, after fractionation, or a combination thereof.32. The method of claim 26, further comprising modifying the conditionsfor dewaxing while performing dewaxing of hydrocracked effluent producedduring the modification of the conditions for hydrocracking.
 33. Themethod of claim 32, wherein the second dewaxing conditions comprisemodified dewaxing conditions, the second dewaxing inlet temperaturecomprising a modified dewaxing inlet temperature.
 34. The method ofclaim 32, further comprising modifying the conditions for dewaxing i)while performing dewaxing of the at least a portion of the firsthydrocracked effluent, ii) while performing dewaxing of the at least aportion of the second hydrocracked effluent, or iii) a combination of i)and ii).